Use mixins and decorators for scroll restoration and tippy cleanup (#2415)

* Enable @babel/plugin-proposal-decorators

Dependency already exists

* Use tippy.js delegate addon, cleanup tippy instances from a mixin.

The delegate addon creates tippy instances from mouse and touch events
with a matching `event.target`. This is initially significantly cheaper
than creating all instances at once. The addon keeps all created tippy
instances alive until it is destroyed itself.

`tippyMixin` destroys the addon instance after every render, as long as
all instances are hidden. This drops some tippy instances that may have
to be recreated later (e.g when the mouse moves over the trigger again),
but is otherwise fairly cheap (creates one tippy instance).

* Restore scroll positions when resource loading settles.

The history module generates a random string (`location.key`) for every
browser history entry. The names for saved positions include this key.
The position is saved before a route component unmounts or before the
`location.key` changes.

The `scrollMixin` tires to restore the scroll position after every
change of `location.key`. It only does so after the first render for
which the route components `loadingSettled()` returns true.

Things like `scrollToComments` should only scroll when `history.action`
is not "POP".

* Drop individual scrollTo calls

* Scroll to comments without reloading post

---------

Co-authored-by: SleeplessOne1917 <28871516+SleeplessOne1917@users.noreply.github.com>

.babelrc

@@ -13,7 +13,12 @@
     ["@babel/typescript", { "isTSX": true, "allExtensions": true }]
   ],
   "plugins": [
-    "@babel/plugin-transform-runtime",
+    ["@babel/plugin-proposal-decorators", { "version": "legacy" }],
+    [
+      "@babel/plugin-transform-runtime",
+      // version defaults to 7.0.0 for which non-legacy decorators produce duplicate code
+      { "version": "^7.24.3" }
+    ],
     ["babel-plugin-inferno", { "imports": true }],
     ["@babel/plugin-transform-class-properties", { "loose": true }]
   ]

.eslintrc.json

@@ -21,6 +21,10 @@
     "@typescript-eslint/explicit-module-boundary-types": 0,
     "@typescript-eslint/no-empty-function": 0,
     "@typescript-eslint/no-non-null-assertion": 0,
+    "@typescript-eslint/no-unused-vars": [
+      "error",
+      { "argsIgnorePattern": "^_" }
+    ],
     "arrow-body-style": 0,
     "curly": 0,
     "eol-last": 0,

src/client/index.tsx

@@ -16,6 +16,8 @@ async function startClient() {
     verifyDynamicImports(true).then(x => console.log(x));
   };
 
+  window.history.scrollRestoration = "manual";
+
   initializeSite(window.isoData.site_res);
 
   lazyHighlightjs.enableLazyLoading();

src/shared/components/app/app.tsx

@@ -13,15 +13,25 @@ import { Navbar } from "./navbar";
 import "./styles.scss";
 import { Theme } from "./theme";
 import AnonymousGuard from "../common/anonymous-guard";
+import { destroyTippy, setupTippy } from "../../tippy";
 
 export class App extends Component<any, any> {
   private isoData: IsoDataOptionalSite = setIsoData(this.context);
   private readonly mainContentRef: RefObject<HTMLElement>;
+  private readonly rootRef = createRef<HTMLDivElement>();
   constructor(props: any, context: any) {
     super(props, context);
     this.mainContentRef = createRef();
   }
 
+  componentDidMount(): void {
+    setupTippy(this.rootRef);
+  }
+
+  componentWillUnmount(): void {
+    destroyTippy();
+  }
+
   handleJumpToContent(event) {
     event.preventDefault();
     this.mainContentRef.current?.focus();
@@ -34,7 +44,7 @@ export class App extends Component<any, any> {
     return (
       <>
         <Provider i18next={I18NextService.i18n}>
-          <div id="app" className="lemmy-site">
+          <div id="app" className="lemmy-site" ref={this.rootRef}>
             <button
               type="button"
               className="btn skip-link bg-light position-absolute start-0 z-3"

src/shared/components/app/navbar.tsx

@@ -15,6 +15,7 @@ import { toast } from "../../toast";
 import { Icon } from "../common/icon";
 import { PictrsImage } from "../common/pictrs-image";
 import { Subscription } from "rxjs";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface NavbarProps {
   siteRes?: GetSiteResponse;
@@ -42,6 +43,7 @@ function handleLogOut(i: Navbar) {
   handleCollapseClick(i);
 }
 
+@tippyMixin
 export class Navbar extends Component<NavbarProps, NavbarState> {
   collapseButtonRef = createRef<HTMLButtonElement>();
   mobileMenuRef = createRef<HTMLDivElement>();

src/shared/components/comment/comment-node.tsx

@@ -42,7 +42,7 @@ import {
 } from "../../interfaces";
 import { mdToHtml, mdToHtmlNoImages } from "../../markdown";
 import { I18NextService, UserService } from "../../services";
-import { setupTippy } from "../../tippy";
+import { tippyMixin } from "../mixins/tippy-mixin";
 import { Icon, Spinner } from "../common/icon";
 import { MomentTime } from "../common/moment-time";
 import { UserBadges } from "../common/user-badges";
@@ -117,6 +117,7 @@ function handleToggleViewSource(i: CommentNode) {
   }));
 }
 
+@tippyMixin
 export class CommentNode extends Component<CommentNodeProps, CommentNodeState> {
   state: CommentNodeState = {
     showReply: false,
@@ -607,12 +608,10 @@ export class CommentNode extends Component<CommentNodeProps, CommentNodeState> {
 
   handleCommentCollapse(i: CommentNode) {
     i.setState({ collapsed: !i.state.collapsed });
-    setupTippy();
   }
 
   handleShowAdvanced(i: CommentNode) {
     i.setState({ showAdvanced: !i.state.showAdvanced });
-    setupTippy();
   }
 
   async handleSaveComment() {

src/shared/components/comment/comment-report.tsx

@@ -11,6 +11,7 @@ import { Icon, Spinner } from "../common/icon";
 import { PersonListing } from "../person/person-listing";
 import { CommentNode } from "./comment-node";
 import { EMPTY_REQUEST } from "../../services/HttpService";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface CommentReportProps {
   report: CommentReportView;
@@ -21,6 +22,7 @@ interface CommentReportState {
   loading: boolean;
 }
 
+@tippyMixin
 export class CommentReport extends Component<
   CommentReportProps,
   CommentReportState

src/shared/components/common/content-actions/action-button.tsx

@@ -1,6 +1,7 @@
 import { Component, linkEvent } from "inferno";
 import { Icon, Spinner } from "../icon";
 import classNames from "classnames";
+import { tippyMixin } from "../../mixins/tippy-mixin";
 
 interface ActionButtonPropsBase {
   label: string;
@@ -34,6 +35,7 @@ async function handleClick(i: ActionButton) {
   i.setState({ loading: false });
 }
 
+@tippyMixin
 export default class ActionButton extends Component<
   ActionButtonProps,
   ActionButtonState

src/shared/components/common/content-actions/content-action-dropdown.tsx

@@ -20,6 +20,7 @@ import ViewVotesModal from "../view-votes-modal";
 import ModActionFormModal, { BanUpdateForm } from "../mod-action-form-modal";
 import { BanType, CommentNodeView, PurgeType } from "../../../interfaces";
 import { getApubName, hostname } from "@utils/helpers";
+import { tippyMixin } from "../../mixins/tippy-mixin";
 
 interface ContentActionDropdownPropsBase {
   onSave: () => Promise<void>;
@@ -76,6 +77,7 @@ type ContentActionDropdownState = {
   mounted: boolean;
 } & { [key in DialogType]: boolean };
 
+@tippyMixin
 export default class ContentActionDropdown extends Component<
   ContentActionDropdownProps,
   ContentActionDropdownState

src/shared/components/common/emoji-picker.tsx

@@ -2,6 +2,7 @@ import { Component, linkEvent } from "inferno";
 import { I18NextService } from "../../services";
 import { EmojiMart } from "./emoji-mart";
 import { Icon } from "./icon";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface EmojiPickerProps {
   onEmojiClick?(val: any): any;
@@ -16,6 +17,7 @@ function closeEmojiMartOnEsc(i, event): void {
   event.key === "Escape" && i.setState({ showPicker: false });
 }
 
+@tippyMixin
 export class EmojiPicker extends Component<EmojiPickerProps, EmojiPickerState> {
   private emptyState: EmojiPickerState = {
     showPicker: false,

src/shared/components/common/markdown-textarea.tsx

@@ -3,7 +3,7 @@ import { numToSI, randomStr } from "@utils/helpers";
 import autosize from "autosize";
 import classNames from "classnames";
 import { NoOptionI18nKeys } from "i18next";
-import { Component, linkEvent } from "inferno";
+import { Component, InfernoNode, linkEvent } from "inferno";
 import { Prompt } from "inferno-router";
 import { Language } from "lemmy-js-client";
 import {
@@ -15,7 +15,7 @@ import {
 } from "../../config";
 import { customEmojisLookup, mdToHtml, setupTribute } from "../../markdown";
 import { HttpService, I18NextService, UserService } from "../../services";
-import { setupTippy } from "../../tippy";
+import { tippyMixin } from "../mixins/tippy-mixin";
 import { pictrsDeleteToast, toast } from "../../toast";
 import { EmojiPicker } from "./emoji-picker";
 import { Icon, Spinner } from "./icon";
@@ -68,6 +68,7 @@ interface MarkdownTextAreaState {
   submitted: boolean;
 }
 
+@tippyMixin
 export class MarkdownTextArea extends Component<
   MarkdownTextAreaProps,
   MarkdownTextAreaState
@@ -111,13 +112,12 @@ export class MarkdownTextArea extends Component<
       if (this.props.focus) {
         textarea.focus();
       }
-
-      // TODO this is slow for some reason
-      setupTippy();
     }
   }
 
-  componentWillReceiveProps(nextProps: MarkdownTextAreaProps) {
+  componentWillReceiveProps(
+    nextProps: MarkdownTextAreaProps & { children?: InfernoNode },
+  ) {
     if (nextProps.finished) {
       this.setState({
         previewMode: false,

src/shared/components/common/moment-time.tsx

@@ -3,6 +3,7 @@ import { format, parseISO } from "date-fns";
 import { Component } from "inferno";
 import { I18NextService } from "../../services";
 import { Icon } from "./icon";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface MomentTimeProps {
   published: string;
@@ -16,6 +17,7 @@ function formatDate(input: string) {
   return format(parsed, "PPPPpppp");
 }
 
+@tippyMixin
 export class MomentTime extends Component<MomentTimeProps, any> {
   constructor(props: any, context: any) {
     super(props, context);

src/shared/components/common/password-input.tsx

@@ -5,6 +5,7 @@ import { Component, FormEventHandler, linkEvent } from "inferno";
 import { NavLink } from "inferno-router";
 import { I18NextService } from "../../services";
 import { Icon } from "./icon";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface PasswordInputProps {
   id: string;
@@ -55,6 +56,7 @@ function handleToggleShow(i: PasswordInput) {
   }));
 }
 
+@tippyMixin
 class PasswordInput extends Component<PasswordInputProps, PasswordInputState> {
   state: PasswordInputState = {
     show: false,

src/shared/components/common/user-badges.tsx

@@ -1,6 +1,7 @@
 import classNames from "classnames";
 import { Component } from "inferno";
 import { I18NextService } from "../../services";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface UserBadgesProps {
   isBanned?: boolean;
@@ -12,7 +13,7 @@ interface UserBadgesProps {
   classNames?: string;
 }
 
-export function getRoleLabelPill({
+function getRoleLabelPill({
   label,
   tooltip,
   classes,
@@ -34,6 +35,7 @@ export function getRoleLabelPill({
   );
 }
 
+@tippyMixin
 export class UserBadges extends Component<UserBadgesProps> {
   render() {
     return (

src/shared/components/common/vote-buttons.tsx

@@ -1,7 +1,7 @@
 import { newVote, showScores } from "@utils/app";
 import { numToSI } from "@utils/helpers";
 import classNames from "classnames";
-import { Component, linkEvent } from "inferno";
+import { Component, InfernoNode, linkEvent } from "inferno";
 import {
   CommentAggregates,
   CreateCommentLike,
@@ -11,6 +11,7 @@ import {
 import { VoteContentType, VoteType } from "../../interfaces";
 import { I18NextService, UserService } from "../../services";
 import { Icon, Spinner } from "../common/icon";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface VoteButtonsProps {
   voteContentType: VoteContentType;
@@ -82,6 +83,7 @@ const handleDownvote = (i: VoteButtons) => {
   }
 };
 
+@tippyMixin
 export class VoteButtonsCompact extends Component<
   VoteButtonsProps,
   VoteButtonsState
@@ -95,7 +97,9 @@ export class VoteButtonsCompact extends Component<
     super(props, context);
   }
 
-  componentWillReceiveProps(nextProps: VoteButtonsProps) {
+  componentWillReceiveProps(
+    nextProps: VoteButtonsProps & { children?: InfernoNode },
+  ) {
     if (this.props !== nextProps) {
       this.setState({
         upvoteLoading: false,
@@ -166,6 +170,7 @@ export class VoteButtonsCompact extends Component<
   }
 }
 
+@tippyMixin
 export class VoteButtons extends Component<VoteButtonsProps, VoteButtonsState> {
   state: VoteButtonsState = {
     upvoteLoading: false,
@@ -176,7 +181,9 @@ export class VoteButtons extends Component<VoteButtonsProps, VoteButtonsState> {
     super(props, context);
   }
 
-  componentWillReceiveProps(nextProps: VoteButtonsProps) {
+  componentWillReceiveProps(
+    nextProps: VoteButtonsProps & { children?: InfernoNode },
+  ) {
     if (this.props !== nextProps) {
       this.setState({
         upvoteLoading: false,

src/shared/components/community/communities.tsx

@@ -4,6 +4,7 @@ import {
   getQueryParams,
   getQueryString,
   numToSI,
+  resourcesSettled,
 } from "@utils/helpers";
 import type { QueryParams } from "@utils/types";
 import { RouteDataResponse } from "@utils/types";
@@ -38,6 +39,7 @@ import { SubscribeButton } from "../common/subscribe-button";
 import { getHttpBaseInternal } from "../../utils/env";
 import { RouteComponentProps } from "inferno-router/dist/Route";
 import { IRoutePropsWithFetch } from "../../routes";
+import { scrollMixin } from "../mixins/scroll-mixin";
 
 type CommunitiesData = RouteDataResponse<{
   listCommunitiesResponse: ListCommunitiesResponse;
@@ -84,6 +86,7 @@ export type CommunitiesFetchConfig = IRoutePropsWithFetch<
   CommunitiesProps
 >;
 
+@scrollMixin
 export class Communities extends Component<
   CommunitiesRouteProps,
   CommunitiesState
@@ -96,6 +99,10 @@ export class Communities extends Component<
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.listCommunitiesResponse]);
+  }
+
   constructor(props: CommunitiesRouteProps, context: any) {
     super(props, context);
     this.handlePageChange = this.handlePageChange.bind(this);
@@ -374,8 +381,6 @@ export class Communities extends Component<
         page,
       }),
     });
-
-    window.scrollTo(0, 0);
   }
 
   findAndUpdateCommunity(res: RequestState<CommunityResponse>) {

src/shared/components/community/community-form.tsx

@@ -13,6 +13,7 @@ import { Icon, Spinner } from "../common/icon";
 import { ImageUploadForm } from "../common/image-upload-form";
 import { LanguageSelect } from "../common/language-select";
 import { MarkdownTextArea } from "../common/markdown-textarea";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface CommunityFormProps {
   community_view?: CommunityView; // If a community is given, that means this is an edit
@@ -40,6 +41,7 @@ interface CommunityFormState {
   submitted: boolean;
 }
 
+@tippyMixin
 export class CommunityForm extends Component<
   CommunityFormProps,
   CommunityFormState

src/shared/components/community/community.tsx

@@ -14,7 +14,12 @@ import {
   updateCommunityBlock,
   updatePersonBlock,
 } from "@utils/app";
-import { getQueryParams, getQueryString } from "@utils/helpers";
+import {
+  getQueryParams,
+  getQueryString,
+  resourcesSettled,
+} from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import type { QueryParams } from "@utils/types";
 import { RouteDataResponse } from "@utils/types";
 import { Component, RefObject, createRef, linkEvent } from "inferno";
@@ -87,7 +92,7 @@ import {
   RequestState,
   wrapClient,
 } from "../../services/HttpService";
-import { setupTippy } from "../../tippy";
+import { tippyMixin } from "../mixins/tippy-mixin";
 import { toast } from "../../toast";
 import { CommentNodes } from "../comment/comment-nodes";
 import { BannerIconHeader } from "../common/banner-icon-header";
@@ -172,6 +177,8 @@ export type CommunityFetchConfig = IRoutePropsWithFetch<
   CommunityProps
 >;
 
+@scrollMixin
+@tippyMixin
 export class Community extends Component<CommunityRouteProps, State> {
   private isoData = setIsoData<CommunityData>(this.context);
   state: State = {
@@ -184,6 +191,16 @@ export class Community extends Component<CommunityRouteProps, State> {
     isIsomorphic: false,
   };
   private readonly mainContentRef: RefObject<HTMLElement>;
+
+  loadingSettled() {
+    return resourcesSettled([
+      this.state.communityRes,
+      this.props.dataType === DataType.Post
+        ? this.state.postsRes
+        : this.state.commentsRes,
+    ]);
+  }
+
   constructor(props: CommunityRouteProps, context: any) {
     super(props, context);
 
@@ -253,8 +270,6 @@ export class Community extends Component<CommunityRouteProps, State> {
     if (!this.state.isIsomorphic) {
       await Promise.all([this.fetchCommunity(), this.fetchData()]);
     }
-
-    setupTippy();
   }
 
   static async fetchInitialData({
@@ -586,17 +601,14 @@ export class Community extends Component<CommunityRouteProps, State> {
 
   handlePageNext(nextPage: PaginationCursor) {
     this.updateUrl({ pageCursor: nextPage });
-    window.scrollTo(0, 0);
   }
 
   handleSortChange(sort: SortType) {
     this.updateUrl({ sort, pageCursor: undefined });
-    window.scrollTo(0, 0);
   }
 
   handleDataTypeChange(dataType: DataType) {
     this.updateUrl({ dataType, pageCursor: undefined });
-    window.scrollTo(0, 0);
   }
 
   handleShowSidebarMobile(i: Community) {
@@ -649,8 +661,6 @@ export class Community extends Component<CommunityRouteProps, State> {
         }),
       });
     }
-
-    setupTippy();
   }
 
   async handleDeleteCommunity(form: DeleteCommunity) {

src/shared/components/community/create-community.tsx

@@ -7,13 +7,19 @@ import {
 import { HttpService, I18NextService } from "../../services";
 import { HtmlTags } from "../common/html-tags";
 import { CommunityForm } from "./community-form";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
+import { RouteComponentProps } from "inferno-router/dist/Route";
 
 interface CreateCommunityState {
   siteRes: GetSiteResponse;
   loading: boolean;
 }
 
-export class CreateCommunity extends Component<any, CreateCommunityState> {
+@simpleScrollMixin
+export class CreateCommunity extends Component<
+  RouteComponentProps<Record<string, never>>,
+  CreateCommunityState
+> {
   private isoData = setIsoData(this.context);
   state: CreateCommunityState = {
     siteRes: this.isoData.site_res,

src/shared/components/community/sidebar.tsx

@@ -25,6 +25,7 @@ import { SubscribeButton } from "../common/subscribe-button";
 import { CommunityForm } from "../community/community-form";
 import { CommunityLink } from "../community/community-link";
 import { PersonListing } from "../person/person-listing";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface SidebarProps {
   community_view: CommunityView;
@@ -60,6 +61,7 @@ interface SidebarState {
   purgeCommunityLoading: boolean;
 }
 
+@tippyMixin
 export class Sidebar extends Component<SidebarProps, SidebarState> {
   state: SidebarState = {
     showEdit: false,

src/shared/components/home/admin-settings.tsx

@@ -1,5 +1,6 @@
 import { fetchThemeList, setIsoData, showLocal } from "@utils/app";
-import { capitalizeFirstLetter } from "@utils/helpers";
+import { capitalizeFirstLetter, resourcesSettled } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { RouteDataResponse } from "@utils/types";
 import classNames from "classnames";
 import { Component, linkEvent } from "inferno";
@@ -62,6 +63,7 @@ export type AdminSettingsFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class AdminSettings extends Component<
   AdminSettingsRouteProps,
   AdminSettingsState
@@ -79,6 +81,10 @@ export class AdminSettings extends Component<
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.bannedRes, this.state.instancesRes]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 

src/shared/components/home/emojis-form.tsx

@@ -13,6 +13,7 @@ import { pictrsDeleteToast, toast } from "../../toast";
 import { EmojiMart } from "../common/emoji-mart";
 import { Icon, Spinner } from "../common/icon";
 import { Paginator } from "../common/paginator";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface EmojiFormProps {
   onEdit(form: EditCustomEmoji): void;
@@ -38,6 +39,7 @@ interface CustomEmojiViewForm {
   loading: boolean;
 }
 
+@tippyMixin
 export class EmojiForm extends Component<EmojiFormProps, EmojiFormState> {
   private isoData = setIsoData(this.context);
   private itemsPerPage = 15;

src/shared/components/home/home.tsx

@@ -17,7 +17,9 @@ import {
   getQueryParams,
   getQueryString,
   getRandomFromList,
+  resourcesSettled,
 } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { canCreateCommunity } from "@utils/roles";
 import type { QueryParams } from "@utils/types";
 import { RouteDataResponse } from "@utils/types";
@@ -87,7 +89,7 @@ import {
   RequestState,
   wrapClient,
 } from "../../services/HttpService";
-import { setupTippy } from "../../tippy";
+import { tippyMixin } from "../mixins/tippy-mixin";
 import { toast } from "../../toast";
 import { CommentNodes } from "../comment/comment-nodes";
 import { DataTypeSelect } from "../common/data-type-select";
@@ -107,6 +109,7 @@ import {
 } from "../common/loading-skeleton";
 import { RouteComponentProps } from "inferno-router/dist/Route";
 import { IRoutePropsWithFetch } from "../../routes";
+import { snapToTop } from "@utils/browser";
 
 interface HomeState {
   postsRes: RequestState<GetPostsResponse>;
@@ -116,7 +119,6 @@ interface HomeState {
   showTrendingMobile: boolean;
   showSidebarMobile: boolean;
   subscribedCollapsed: boolean;
-  scrolled: boolean;
   tagline?: string;
   siteRes: GetSiteResponse;
   finished: Map<CommentId, boolean | undefined>;
@@ -253,13 +255,14 @@ export type HomeFetchConfig = IRoutePropsWithFetch<
   HomeProps
 >;
 
+@scrollMixin
+@tippyMixin
 export class Home extends Component<HomeRouteProps, HomeState> {
   private isoData = setIsoData<HomeData>(this.context);
   state: HomeState = {
     postsRes: EMPTY_REQUEST,
     commentsRes: EMPTY_REQUEST,
     trendingCommunitiesRes: EMPTY_REQUEST,
-    scrolled: true,
     siteRes: this.isoData.site_res,
     showSubscribedMobile: false,
     showTrendingMobile: false,
@@ -269,6 +272,15 @@ export class Home extends Component<HomeRouteProps, HomeState> {
     isIsomorphic: false,
   };
 
+  loadingSettled(): boolean {
+    return resourcesSettled([
+      this.state.trendingCommunitiesRes,
+      this.props.dataType === DataType.Post
+        ? this.state.postsRes
+        : this.state.commentsRes,
+    ]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 
@@ -334,8 +346,6 @@ export class Home extends Component<HomeRouteProps, HomeState> {
     ) {
       await Promise.all([this.fetchTrendingCommunities(), this.fetchData()]);
     }
-
-    setupTippy();
   }
 
   static async fetchInitialData({
@@ -667,11 +677,6 @@ export class Home extends Component<HomeRouteProps, HomeState> {
       search: getQueryString(queryParams),
     });
 
-    if (!this.state.scrolled) {
-      this.setState({ scrolled: true });
-      setTimeout(() => window.scrollTo(0, 0), 0);
-    }
-
     await this.fetchData();
   }
 
@@ -852,8 +857,6 @@ export class Home extends Component<HomeRouteProps, HomeState> {
         }),
       });
     }
-
-    setupTippy();
   }
 
   handleShowSubscribedMobile(i: Home) {
@@ -876,27 +879,23 @@ export class Home extends Component<HomeRouteProps, HomeState> {
     this.props.history.back();
     // A hack to scroll to top
     setTimeout(() => {
-      window.scrollTo(0, 0);
+      snapToTop();
     }, 50);
   }
 
   handlePageNext(nextPage: PaginationCursor) {
-    this.setState({ scrolled: false });
     this.updateUrl({ pageCursor: nextPage });
   }
 
   handleSortChange(val: SortType) {
-    this.setState({ scrolled: false });
     this.updateUrl({ sort: val, pageCursor: undefined });
   }
 
   handleListingTypeChange(val: ListingType) {
-    this.setState({ scrolled: false });
     this.updateUrl({ listingType: val, pageCursor: undefined });
   }
 
   handleDataTypeChange(val: DataType) {
-    this.setState({ scrolled: false });
     this.updateUrl({ dataType: val, pageCursor: undefined });
   }
 

src/shared/components/home/instances.tsx

@@ -24,6 +24,8 @@ import Tabs from "../common/tabs";
 import { getHttpBaseInternal } from "../../utils/env";
 import { RouteComponentProps } from "inferno-router/dist/Route";
 import { IRoutePropsWithFetch } from "../../routes";
+import { resourcesSettled } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 
 type InstancesData = RouteDataResponse<{
   federatedInstancesResponse: GetFederatedInstancesResponse;
@@ -43,6 +45,7 @@ export type InstancesFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class Instances extends Component<InstancesRouteProps, InstancesState> {
   private isoData = setIsoData<InstancesData>(this.context);
   state: InstancesState = {
@@ -51,6 +54,10 @@ export class Instances extends Component<InstancesRouteProps, InstancesState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.instancesRes]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 

src/shared/components/home/login-reset.tsx

@@ -6,6 +6,8 @@ import { HttpService, I18NextService } from "../../services";
 import { toast } from "../../toast";
 import { HtmlTags } from "../common/html-tags";
 import { Spinner } from "../common/icon";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
+import { RouteComponentProps } from "inferno-router/dist/Route";
 
 interface State {
   form: {
@@ -15,7 +17,11 @@ interface State {
   siteRes: GetSiteResponse;
 }
 
-export class LoginReset extends Component<any, State> {
+@simpleScrollMixin
+export class LoginReset extends Component<
+  RouteComponentProps<Record<string, never>>,
+  State
+> {
   private isoData = setIsoData(this.context);
 
   state: State = {

src/shared/components/home/login.tsx

@@ -19,6 +19,7 @@ import TotpModal from "../common/totp-modal";
 import { UnreadCounterService } from "../../services";
 import { RouteData } from "../../interfaces";
 import { IRoutePropsWithFetch } from "../../routes";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
 
 interface LoginProps {
   prev?: string;
@@ -125,6 +126,7 @@ export type LoginFetchConfig = IRoutePropsWithFetch<
   LoginProps
 >;
 
+@simpleScrollMixin
 export class Login extends Component<LoginRouteProps, State> {
   private isoData = setIsoData(this.context);
 

src/shared/components/home/setup.tsx

@@ -17,6 +17,8 @@ import {
 import { Spinner } from "../common/icon";
 import PasswordInput from "../common/password-input";
 import { SiteForm } from "./site-form";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
+import { RouteComponentProps } from "inferno-router/dist/Route";
 
 interface State {
   form: {
@@ -36,7 +38,11 @@ interface State {
   siteRes: GetSiteResponse;
 }
 
-export class Setup extends Component<any, State> {
+@simpleScrollMixin
+export class Setup extends Component<
+  RouteComponentProps<Record<string, never>>,
+  State
+> {
   private isoData = setIsoData(this.context);
 
   state: State = {

src/shared/components/home/signup.tsx

@@ -1,6 +1,7 @@
 import { setIsoData } from "@utils/app";
 import { isBrowser } from "@utils/browser";
-import { validEmail } from "@utils/helpers";
+import { resourcesSettled, validEmail } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { Component, linkEvent } from "inferno";
 import { T } from "inferno-i18next-dess";
 import {
@@ -24,6 +25,7 @@ import { HtmlTags } from "../common/html-tags";
 import { Icon, Spinner } from "../common/icon";
 import { MarkdownTextArea } from "../common/markdown-textarea";
 import PasswordInput from "../common/password-input";
+import { RouteComponentProps } from "inferno-router/dist/Route";
 
 interface State {
   registerRes: RequestState<LoginResponse>;
@@ -43,7 +45,11 @@ interface State {
   siteRes: GetSiteResponse;
 }
 
-export class Signup extends Component<any, State> {
+@scrollMixin
+export class Signup extends Component<
+  RouteComponentProps<Record<string, never>>,
+  State
+> {
   private isoData = setIsoData(this.context);
   private audio?: HTMLAudioElement;
 
@@ -57,6 +63,13 @@ export class Signup extends Component<any, State> {
     siteRes: this.isoData.site_res,
   };
 
+  loadingSettled() {
+    return (
+      !this.state.siteRes.site_view.local_site.captcha_enabled ||
+      resourcesSettled([this.state.captchaRes])
+    );
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 

src/shared/components/home/site-sidebar.tsx

@@ -7,6 +7,7 @@ import { Badges } from "../common/badges";
 import { BannerIconHeader } from "../common/banner-icon-header";
 import { Icon } from "../common/icon";
 import { PersonListing } from "../person/person-listing";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface SiteSidebarProps {
   site: Site;
@@ -20,6 +21,7 @@ interface SiteSidebarState {
   collapsed: boolean;
 }
 
+@tippyMixin
 export class SiteSidebar extends Component<SiteSidebarProps, SiteSidebarState> {
   state: SiteSidebarState = {
     collapsed: false,

src/shared/components/home/tagline-form.tsx

@@ -4,6 +4,7 @@ import { EditSite, Tagline } from "lemmy-js-client";
 import { I18NextService } from "../../services";
 import { Icon, Spinner } from "../common/icon";
 import { MarkdownTextArea } from "../common/markdown-textarea";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface TaglineFormProps {
   taglines: Array<Tagline>;
@@ -16,6 +17,7 @@ interface TaglineFormState {
   editingRow?: number;
 }
 
+@tippyMixin
 export class TaglineForm extends Component<TaglineFormProps, TaglineFormState> {
   state: TaglineFormState = {
     editingRow: undefined,

src/shared/components/mixins/scroll-mixin.ts

@@ -0,0 +1,145 @@
+import { isBrowser, nextUserAction, snapToTop } from "../../utils/browser";
+import { Component, InfernoNode } from "inferno";
+import { Location } from "history";
+
+function restoreScrollPosition(props: { location: Location }) {
+  const key: string = props.location.key;
+  const y = sessionStorage.getItem(`scrollPosition_${key}`);
+
+  if (y !== null) {
+    window.scrollTo({ left: 0, top: Number(y), behavior: "instant" });
+  }
+}
+
+function saveScrollPosition(props: { location: Location }) {
+  const key: string = props.location.key;
+
+  const y = window.scrollY;
+
+  sessionStorage.setItem(`scrollPosition_${key}`, y.toString());
+}
+
+function dropScrollPosition(props: { location: Location }) {
+  const key: string = props.location.key;
+  sessionStorage.removeItem(`scrollPosition_${key}`);
+}
+
+export function scrollMixin<
+  P extends { location: Location },
+  S,
+  Base extends new (
+    ...args: any
+  ) => Component<P, S> & { loadingSettled(): boolean },
+>(base: Base, _context?: ClassDecoratorContext<Base>) {
+  return class extends base {
+    private stopUserListener: (() => void) | undefined;
+    private blocked?: string;
+
+    constructor(...args: any[]) {
+      super(...args);
+
+      if (!isBrowser()) {
+        return;
+      }
+
+      this.reset();
+    }
+
+    componentDidMount() {
+      this.restoreIfLoaded();
+      return super.componentDidMount?.();
+    }
+
+    componentDidUpdate(
+      prevProps: Readonly<{ children?: InfernoNode } & P>,
+      prevState: S,
+      snapshot: any,
+    ) {
+      this.restoreIfLoaded();
+      return super.componentDidUpdate?.(prevProps, prevState, snapshot);
+    }
+
+    componentWillUnmount() {
+      this.saveFinalPosition();
+      return super.componentWillUnmount?.();
+    }
+
+    componentWillReceiveProps(
+      nextProps: Readonly<{ children?: InfernoNode } & P>,
+      nextContext: any,
+    ) {
+      // Currently this is hypothetical. Components unmount before route changes.
+      if (this.props.location.key !== nextProps.location.key) {
+        this.saveFinalPosition();
+        this.reset();
+      }
+      return super.componentWillReceiveProps?.(nextProps, nextContext);
+    }
+
+    unloadListeners = () => {
+      // Browsers restore the position after reload, but not after pressing
+      // Enter in the url bar. It's hard to distinguish the two, let the
+      // browser do its thing.
+      window.history.scrollRestoration = "auto";
+      dropScrollPosition(this.props);
+    };
+
+    reset() {
+      this.blocked = undefined;
+      this.stopUserListener?.();
+      // While inferno is rendering no events are dispatched. This only catches
+      // user interactions when network responses are slow/late.
+      this.stopUserListener = nextUserAction(() => {
+        this.preventRestore();
+      });
+      window.removeEventListener("beforeunload", this.unloadListeners);
+      window.addEventListener("beforeunload", this.unloadListeners);
+    }
+
+    savePosition() {
+      saveScrollPosition(this.props);
+    }
+
+    saveFinalPosition() {
+      this.savePosition();
+      snapToTop();
+      window.removeEventListener("beforeunload", this.unloadListeners);
+    }
+
+    preventRestore() {
+      this.blocked = this.props.location.key;
+      this.stopUserListener?.();
+      this.stopUserListener = undefined;
+    }
+
+    restore() {
+      restoreScrollPosition(this.props);
+      this.preventRestore();
+    }
+
+    restoreIfLoaded() {
+      if (!this.isPending() || !this.loadingSettled()) {
+        return;
+      }
+      this.restore();
+    }
+
+    isPending() {
+      return this.blocked !== this.props.location.key;
+    }
+  };
+}
+
+export function simpleScrollMixin<
+  P extends { location: Location },
+  S,
+  Base extends new (...args: any) => Component<P, S>,
+>(base: Base, _context?: ClassDecoratorContext<Base>) {
+  @scrollMixin
+  class SimpleScrollMixin extends base {
+    loadingSettled() {
+      return true;
+    }
+  }
+  return SimpleScrollMixin;
+}

src/shared/components/mixins/tippy-mixin.ts

@@ -0,0 +1,25 @@
+import { Component, InfernoNode } from "inferno";
+import { cleanupTippy } from "../../tippy";
+
+export function tippyMixin<
+  P,
+  S,
+  Base extends new (...args: any) => Component<P, S>,
+>(base: Base, _context?: ClassDecoratorContext<Base>) {
+  return class extends base {
+    componentDidUpdate(
+      prevProps: P & { children?: InfernoNode },
+      prevState: S,
+      snapshot: any,
+    ) {
+      // For conditional rendering, old tippy instances aren't reused
+      cleanupTippy();
+      return super.componentDidUpdate?.(prevProps, prevState, snapshot);
+    }
+
+    componentWillUnmount() {
+      cleanupTippy();
+      return super.componentWillUnmount?.();
+    }
+  };
+}

src/shared/components/modlog.tsx

@@ -11,7 +11,9 @@ import {
   getPageFromString,
   getQueryParams,
   getQueryString,
+  resourcesSettled,
 } from "@utils/helpers";
+import { scrollMixin } from "./mixins/scroll-mixin";
 import { amAdmin, amMod } from "@utils/roles";
 import type { QueryParams } from "@utils/types";
 import { Choice, RouteDataResponse } from "@utils/types";
@@ -645,6 +647,7 @@ export type ModlogFetchConfig = IRoutePropsWithFetch<
   ModlogProps
 >;
 
+@scrollMixin
 export class Modlog extends Component<ModlogRouteProps, ModlogState> {
   private isoData = setIsoData<ModlogData>(this.context);
 
@@ -658,6 +661,10 @@ export class Modlog extends Component<ModlogRouteProps, ModlogState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.res]);
+  }
+
   constructor(props: ModlogRouteProps, context: any) {
     super(props, context);
     this.handlePageChange = this.handlePageChange.bind(this);

src/shared/components/person/cake-day.tsx

@@ -1,11 +1,13 @@
 import { Component } from "inferno";
 import { I18NextService } from "../../services";
 import { Icon } from "../common/icon";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface CakeDayProps {
   creatorName: string;
 }
 
+@tippyMixin
 export class CakeDay extends Component<CakeDayProps, any> {
   render() {
     return (

src/shared/components/person/inbox.tsx

@@ -10,7 +10,12 @@ import {
   setIsoData,
   updatePersonBlock,
 } from "@utils/app";
-import { capitalizeFirstLetter, randomStr } from "@utils/helpers";
+import {
+  capitalizeFirstLetter,
+  randomStr,
+  resourcesSettled,
+} from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { RouteDataResponse } from "@utils/types";
 import classNames from "classnames";
 import { Component, linkEvent } from "inferno";
@@ -137,6 +142,7 @@ export type InboxFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class Inbox extends Component<InboxRouteProps, InboxState> {
   private isoData = setIsoData<InboxData>(this.context);
   state: InboxState = {
@@ -153,6 +159,14 @@ export class Inbox extends Component<InboxRouteProps, InboxState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([
+      this.state.repliesRes,
+      this.state.mentionsRes,
+      this.state.messagesRes,
+    ]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 

src/shared/components/person/password-change.tsx

@@ -12,6 +12,8 @@ import { HtmlTags } from "../common/html-tags";
 import { Spinner } from "../common/icon";
 import PasswordInput from "../common/password-input";
 import { toast } from "../../toast";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
+import { RouteComponentProps } from "inferno-router/dist/Route";
 
 interface State {
   passwordChangeRes: RequestState<SuccessResponse>;
@@ -23,7 +25,11 @@ interface State {
   siteRes: GetSiteResponse;
 }
 
-export class PasswordChange extends Component<any, State> {
+@simpleScrollMixin
+export class PasswordChange extends Component<
+  RouteComponentProps<Record<string, never>>,
+  State
+> {
   private isoData = setIsoData(this.context);
 
   state: State = {

src/shared/components/person/person-details.tsx

@@ -41,7 +41,6 @@ import {
   TransferCommunity,
 } from "lemmy-js-client";
 import { CommentViewType, PersonDetailsView } from "../../interfaces";
-import { setupTippy } from "../../tippy";
 import { CommentNodes } from "../comment/comment-nodes";
 import { Paginator } from "../common/paginator";
 import { PostListing } from "../post/post-listing";
@@ -109,10 +108,6 @@ export class PersonDetails extends Component<PersonDetailsProps, any> {
     this.handlePageChange = this.handlePageChange.bind(this);
   }
 
-  componentDidMount() {
-    setupTippy();
-  }
-
   render() {
     return (
       <div className="person-details">

src/shared/components/person/profile.tsx

@@ -8,7 +8,7 @@ import {
   setIsoData,
   updatePersonBlock,
 } from "@utils/app";
-import { restoreScrollPosition, saveScrollPosition } from "@utils/browser";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import {
   capitalizeFirstLetter,
   futureDaysToUnixTime,
@@ -17,6 +17,7 @@ import {
   getQueryString,
   numToSI,
   randomStr,
+  resourcesSettled,
 } from "@utils/helpers";
 import { canMod, isBanned } from "@utils/roles";
 import type { QueryParams } from "@utils/types";
@@ -82,7 +83,6 @@ import {
   RequestState,
   wrapClient,
 } from "../../services/HttpService";
-import { setupTippy } from "../../tippy";
 import { toast } from "../../toast";
 import { BannerIconHeader } from "../common/banner-icon-header";
 import { HtmlTags } from "../common/html-tags";
@@ -183,6 +183,7 @@ export type ProfileFetchConfig = IRoutePropsWithFetch<
   ProfileProps
 >;
 
+@scrollMixin
 export class Profile extends Component<ProfileRouteProps, ProfileState> {
   private isoData = setIsoData<ProfileData>(this.context);
   state: ProfileState = {
@@ -195,6 +196,10 @@ export class Profile extends Component<ProfileRouteProps, ProfileState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.personRes]);
+  }
+
   constructor(props: ProfileRouteProps, context: any) {
     super(props, context);
 
@@ -249,11 +254,6 @@ export class Profile extends Component<ProfileRouteProps, ProfileState> {
     if (!this.state.isIsomorphic) {
       await this.fetchUserData();
     }
-    setupTippy();
-  }
-
-  componentWillUnmount() {
-    saveScrollPosition(this.context);
   }
 
   async fetchUserData() {
@@ -271,7 +271,6 @@ export class Profile extends Component<ProfileRouteProps, ProfileState> {
       personRes,
       personBlocked: isPersonBlocked(personRes),
     });
-    restoreScrollPosition(this.context);
   }
 
   get amCurrentUser() {

src/shared/components/person/registration-applications.tsx

@@ -1,5 +1,6 @@
 import { editRegistrationApplication, setIsoData } from "@utils/app";
-import { randomStr } from "@utils/helpers";
+import { randomStr, resourcesSettled } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { RouteDataResponse } from "@utils/types";
 import classNames from "classnames";
 import { Component, linkEvent } from "inferno";
@@ -20,7 +21,6 @@ import {
   RequestState,
   wrapClient,
 } from "../../services/HttpService";
-import { setupTippy } from "../../tippy";
 import { HtmlTags } from "../common/html-tags";
 import { Spinner } from "../common/icon";
 import { Paginator } from "../common/paginator";
@@ -58,6 +58,7 @@ export type RegistrationApplicationsFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class RegistrationApplications extends Component<
   RegistrationApplicationsRouteProps,
   RegistrationApplicationsState
@@ -71,6 +72,10 @@ export class RegistrationApplications extends Component<
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.appsRes]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 
@@ -91,7 +96,6 @@ export class RegistrationApplications extends Component<
     if (!this.state.isIsomorphic) {
       await this.refetch();
     }
-    setupTippy();
   }
 
   get documentTitle(): string {

src/shared/components/person/reports.tsx

@@ -4,7 +4,8 @@ import {
   editPrivateMessageReport,
   setIsoData,
 } from "@utils/app";
-import { randomStr } from "@utils/helpers";
+import { randomStr, resourcesSettled } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { amAdmin } from "@utils/roles";
 import { RouteDataResponse } from "@utils/types";
 import classNames from "classnames";
@@ -103,6 +104,7 @@ export type ReportsFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class Reports extends Component<ReportsRouteProps, ReportsState> {
   private isoData = setIsoData<ReportsData>(this.context);
   state: ReportsState = {
@@ -116,6 +118,14 @@ export class Reports extends Component<ReportsRouteProps, ReportsState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([
+      this.state.commentReportsRes,
+      this.state.postReportsRes,
+      this.state.messageReportsRes,
+    ]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 

src/shared/components/person/settings.tsx

@@ -49,7 +49,7 @@ import {
   languages,
   loadUserLanguage,
 } from "../../services/I18NextService";
-import { setupTippy } from "../../tippy";
+import { tippyMixin } from "../mixins/tippy-mixin";
 import { toast } from "../../toast";
 import { HtmlTags } from "../common/html-tags";
 import { Icon, Spinner } from "../common/icon";
@@ -66,10 +66,11 @@ import { PersonListing } from "./person-listing";
 import { InitialFetchRequest } from "../../interfaces";
 import TotpModal from "../common/totp-modal";
 import { LoadingEllipses } from "../common/loading-ellipses";
-import { refreshTheme, setThemeOverride } from "../../utils/browser";
+import { refreshTheme, setThemeOverride, snapToTop } from "../../utils/browser";
 import { getHttpBaseInternal } from "../../utils/env";
 import { IRoutePropsWithFetch } from "../../routes";
 import { RouteComponentProps } from "inferno-router/dist/Route";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
 
 type SettingsData = RouteDataResponse<{
   instancesRes: GetFederatedInstancesResponse;
@@ -203,6 +204,8 @@ export type SettingsFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@simpleScrollMixin
+@tippyMixin
 export class Settings extends Component<SettingsRouteProps, SettingsState> {
   private isoData = setIsoData<SettingsData>(this.context);
   exportSettingsLink = createRef<HTMLAnchorElement>();
@@ -334,7 +337,6 @@ export class Settings extends Component<SettingsRouteProps, SettingsState> {
   }
 
   async componentDidMount() {
-    setupTippy();
     this.setState({ themeList: await fetchThemeList() });
 
     if (!this.state.isIsomorphic) {
@@ -1578,7 +1580,7 @@ export class Settings extends Component<SettingsRouteProps, SettingsState> {
       }
 
       toast(I18NextService.i18n.t("saved"));
-      window.scrollTo(0, 0);
+      snapToTop();
     }
 
     setThemeOverride(undefined);
@@ -1598,7 +1600,7 @@ export class Settings extends Component<SettingsRouteProps, SettingsState> {
         old_password,
       });
       if (changePasswordRes.state === "success") {
-        window.scrollTo(0, 0);
+        snapToTop();
         toast(I18NextService.i18n.t("password_changed"));
       }
 

src/shared/components/person/verify-email.tsx

@@ -11,13 +11,19 @@ import {
 import { toast } from "../../toast";
 import { HtmlTags } from "../common/html-tags";
 import { Spinner } from "../common/icon";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
+import { RouteComponentProps } from "inferno-router/dist/Route";
 
 interface State {
   verifyRes: RequestState<SuccessResponse>;
   siteRes: GetSiteResponse;
 }
 
-export class VerifyEmail extends Component<any, State> {
+@simpleScrollMixin
+export class VerifyEmail extends Component<
+  RouteComponentProps<Record<string, never>>,
+  State
+> {
   private isoData = setIsoData(this.context);
 
   state: State = {

src/shared/components/post/create-post.tsx

@@ -30,6 +30,7 @@ import { Spinner } from "../common/icon";
 import { PostForm } from "./post-form";
 import { getHttpBaseInternal } from "../../utils/env";
 import { IRoutePropsWithFetch } from "../../routes";
+import { simpleScrollMixin } from "../mixins/scroll-mixin";
 
 export interface CreatePostProps {
   communityId?: number;
@@ -70,6 +71,7 @@ export type CreatePostFetchConfig = IRoutePropsWithFetch<
   CreatePostProps
 >;
 
+@simpleScrollMixin
 export class CreatePost extends Component<
   CreatePostRouteProps,
   CreatePostState

src/shared/components/post/post-form.tsx

@@ -37,7 +37,6 @@ import {
   LOADING_REQUEST,
   RequestState,
 } from "../../services/HttpService";
-import { setupTippy } from "../../tippy";
 import { toast } from "../../toast";
 import { Icon, Spinner } from "../common/icon";
 import { LanguageSelect } from "../common/language-select";
@@ -306,7 +305,6 @@ export class PostForm extends Component<PostFormProps, PostFormState> {
   }
 
   componentDidMount() {
-    setupTippy();
     const textarea: any = document.getElementById("post-title");
 
     if (textarea) {

src/shared/components/post/post-listing.tsx

@@ -35,7 +35,7 @@ import { relTags } from "../../config";
 import { VoteContentType } from "../../interfaces";
 import { mdToHtml, mdToHtmlInline } from "../../markdown";
 import { I18NextService, UserService } from "../../services";
-import { setupTippy } from "../../tippy";
+import { tippyMixin } from "../mixins/tippy-mixin";
 import { Icon } from "../common/icon";
 import { MomentTime } from "../common/moment-time";
 import { PictrsImage } from "../common/pictrs-image";
@@ -91,8 +91,10 @@ interface PostListingProps {
   onAddAdmin(form: AddAdmin): Promise<void>;
   onTransferCommunity(form: TransferCommunity): Promise<void>;
   onMarkPostAsRead(form: MarkPostAsRead): void;
+  onScrollIntoCommentsClick?(e: MouseEvent): void;
 }
 
+@tippyMixin
 export class PostListing extends Component<PostListingProps, PostListingState> {
   state: PostListingState = {
     showEdit: false,
@@ -636,6 +638,7 @@ export class PostListing extends Component<PostListingProps, PostListingState> {
         title={title}
         to={`/post/${pv.post.id}?scrollToComments=true`}
         data-tippy-content={title}
+        onClick={this.props.onScrollIntoCommentsClick}
       >
         <Icon icon="message-square" classes="me-1" inline />
         {pv.counts.comments}
@@ -982,7 +985,6 @@ export class PostListing extends Component<PostListingProps, PostListingState> {
   handleImageExpandClick(i: PostListing, event: any) {
     event.preventDefault();
     i.setState({ imageExpanded: !i.state.imageExpanded });
-    setupTippy();
 
     if (myAuth() && !i.postView.read) {
       i.props.onMarkPostAsRead({
@@ -998,7 +1000,6 @@ export class PostListing extends Component<PostListingProps, PostListingState> {
 
   handleShowBody(i: PostListing) {
     i.setState({ showBody: !i.state.showBody });
-    setupTippy();
   }
 
   get pointsTippy(): string {

src/shared/components/post/post-report.tsx

@@ -6,6 +6,7 @@ import { Icon, Spinner } from "../common/icon";
 import { PersonListing } from "../person/person-listing";
 import { PostListing } from "./post-listing";
 import { EMPTY_REQUEST } from "../../services/HttpService";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface PostReportProps {
   report: PostReportView;
@@ -16,6 +17,7 @@ interface PostReportState {
   loading: boolean;
 }
 
+@tippyMixin
 export class PostReport extends Component<PostReportProps, PostReportState> {
   state: PostReportState = {
     loading: false,

src/shared/components/post/post.tsx

@@ -13,12 +13,14 @@ import {
   updateCommunityBlock,
   updatePersonBlock,
 } from "@utils/app";
+import { isBrowser } from "@utils/browser";
 import {
-  isBrowser,
-  restoreScrollPosition,
-  saveScrollPosition,
-} from "@utils/browser";
-import { debounce, getApubName, randomStr } from "@utils/helpers";
+  debounce,
+  getApubName,
+  randomStr,
+  resourcesSettled,
+} from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 import { isImage } from "@utils/media";
 import { RouteDataResponse } from "@utils/types";
 import autosize from "autosize";
@@ -89,7 +91,6 @@ import {
   RequestState,
   wrapClient,
 } from "../../services/HttpService";
-import { setupTippy } from "../../tippy";
 import { toast } from "../../toast";
 import { CommentForm } from "../comment/comment-form";
 import { CommentNodes } from "../comment/comment-nodes";
@@ -135,6 +136,7 @@ export type PostFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class Post extends Component<PostRouteProps, PostState> {
   private isoData = setIsoData<PostData>(this.context);
   private commentScrollDebounced: () => void;
@@ -153,6 +155,10 @@ export class Post extends Component<PostRouteProps, PostState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.postRes, this.state.commentsRes]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
 
@@ -189,6 +195,8 @@ export class Post extends Component<PostRouteProps, PostState> {
     this.handleSavePost = this.handleSavePost.bind(this);
     this.handlePurgePost = this.handlePurgePost.bind(this);
     this.handleFeaturePost = this.handleFeaturePost.bind(this);
+    this.handleScrollIntoCommentsClick =
+      this.handleScrollIntoCommentsClick.bind(this);
 
     this.state = { ...this.state, commentSectionRef: createRef() };
 
@@ -237,10 +245,6 @@ export class Post extends Component<PostRouteProps, PostState> {
       commentsRes,
     });
 
-    setupTippy();
-
-    if (!this.state.commentId) restoreScrollPosition(this.context);
-
     if (this.checkScrollIntoCommentsParam) {
       this.scrollIntoCommentSection();
     }
@@ -284,8 +288,6 @@ export class Post extends Component<PostRouteProps, PostState> {
 
   componentWillUnmount() {
     document.removeEventListener("scroll", this.commentScrollDebounced);
-
-    saveScrollPosition(this.context);
   }
 
   async componentDidMount() {
@@ -299,16 +301,16 @@ export class Post extends Component<PostRouteProps, PostState> {
     document.addEventListener("scroll", this.commentScrollDebounced);
   }
 
-  async componentDidUpdate(_lastProps: any) {
-    // Necessary if you are on a post and you click another post (same route)
-    if (_lastProps.location.pathname !== _lastProps.history.location.pathname) {
-      await this.fetchPost();
-    }
+  handleScrollIntoCommentsClick(e: MouseEvent) {
+    this.scrollIntoCommentSection();
+    e.preventDefault();
   }
 
   get checkScrollIntoCommentsParam() {
-    return Boolean(
-      new URLSearchParams(this.props.location.search).get("scrollToComments"),
+    return (
+      Boolean(
+        new URLSearchParams(this.props.location.search).get("scrollToComments"),
+      ) && this.props.history.action !== "POP"
     );
   }
 
@@ -403,6 +405,7 @@ export class Post extends Component<PostRouteProps, PostState> {
                 onTransferCommunity={this.handleTransferCommunity}
                 onFeaturePost={this.handleFeaturePost}
                 onMarkPostAsRead={() => {}}
+                onScrollIntoCommentsClick={this.handleScrollIntoCommentsClick}
               />
               <div ref={this.state.commentSectionRef} className="mb-2" />
 

src/shared/components/private_message/create-private-message.tsx

@@ -24,6 +24,8 @@ import { PrivateMessageForm } from "./private-message-form";
 import { getHttpBaseInternal } from "../../utils/env";
 import { RouteComponentProps } from "inferno-router/dist/Route";
 import { IRoutePropsWithFetch } from "../../routes";
+import { resourcesSettled } from "@utils/helpers";
+import { scrollMixin } from "../mixins/scroll-mixin";
 
 type CreatePrivateMessageData = RouteDataResponse<{
   recipientDetailsResponse: GetPersonDetailsResponse;
@@ -45,6 +47,7 @@ export type CreatePrivateMessageFetchConfig = IRoutePropsWithFetch<
   Record<string, never>
 >;
 
+@scrollMixin
 export class CreatePrivateMessage extends Component<
   CreatePrivateMessageRouteProps,
   CreatePrivateMessageState
@@ -57,6 +60,10 @@ export class CreatePrivateMessage extends Component<
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.recipientRes]);
+  }
+
   constructor(props: any, context: any) {
     super(props, context);
     this.handlePrivateMessageCreate =

src/shared/components/private_message/private-message-form.tsx

@@ -10,7 +10,6 @@ import {
 } from "lemmy-js-client";
 import { relTags } from "../../config";
 import { I18NextService } from "../../services";
-import { setupTippy } from "../../tippy";
 import { Icon } from "../common/icon";
 import { MarkdownTextArea } from "../common/markdown-textarea";
 import { PersonListing } from "../person/person-listing";
@@ -50,10 +49,6 @@ export class PrivateMessageForm extends Component<
     this.handleContentChange = this.handleContentChange.bind(this);
   }
 
-  componentDidMount() {
-    setupTippy();
-  }
-
   componentWillReceiveProps(
     nextProps: Readonly<{ children?: InfernoNode } & PrivateMessageFormProps>,
   ): void {

src/shared/components/private_message/private-message-report.tsx

@@ -8,6 +8,7 @@ import { mdToHtml } from "../../markdown";
 import { I18NextService } from "../../services";
 import { Icon, Spinner } from "../common/icon";
 import { PersonListing } from "../person/person-listing";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface Props {
   report: PrivateMessageReportView;
@@ -18,6 +19,7 @@ interface State {
   loading: boolean;
 }
 
+@tippyMixin
 export class PrivateMessageReport extends Component<Props, State> {
   state: State = {
     loading: false,

src/shared/components/private_message/private-message.tsx

@@ -15,6 +15,7 @@ import { MomentTime } from "../common/moment-time";
 import { PersonListing } from "../person/person-listing";
 import { PrivateMessageForm } from "./private-message-form";
 import ModActionFormModal from "../common/mod-action-form-modal";
+import { tippyMixin } from "../mixins/tippy-mixin";
 
 interface PrivateMessageState {
   showReply: boolean;
@@ -35,6 +36,7 @@ interface PrivateMessageProps {
   onEdit(form: EditPrivateMessage): void;
 }
 
+@tippyMixin
 export class PrivateMessage extends Component<
   PrivateMessageProps,
   PrivateMessageState

src/shared/components/remote-fetch.tsx

@@ -1,5 +1,6 @@
 import { setIsoData } from "@utils/app";
-import { getQueryParams } from "@utils/helpers";
+import { getQueryParams, resourcesSettled } from "@utils/helpers";
+import { scrollMixin } from "./mixins/scroll-mixin";
 import { RouteDataResponse } from "@utils/types";
 import { Component, linkEvent } from "inferno";
 import {
@@ -97,6 +98,7 @@ export type RemoteFetchFetchConfig = IRoutePropsWithFetch<
   RemoteFetchProps
 >;
 
+@scrollMixin
 export class RemoteFetch extends Component<
   RemoteFetchRouteProps,
   RemoteFetchState
@@ -108,6 +110,10 @@ export class RemoteFetch extends Component<
     followCommunityLoading: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.resolveObjectRes]);
+  }
+
   constructor(props: RemoteFetchRouteProps, context: any) {
     super(props, context);
 

src/shared/components/search.tsx

@@ -11,7 +11,7 @@ import {
   setIsoData,
   showLocal,
 } from "@utils/app";
-import { restoreScrollPosition, saveScrollPosition } from "@utils/browser";
+import { scrollMixin } from "./mixins/scroll-mixin";
 import {
   capitalizeFirstLetter,
   debounce,
@@ -21,6 +21,7 @@ import {
   getQueryParams,
   getQueryString,
   numToSI,
+  resourcesSettled,
 } from "@utils/helpers";
 import type { QueryParams } from "@utils/types";
 import { Choice, RouteDataResponse } from "@utils/types";
@@ -253,6 +254,7 @@ export type SearchFetchConfig = IRoutePropsWithFetch<
   SearchProps
 >;
 
+@scrollMixin
 export class Search extends Component<SearchRouteProps, SearchState> {
   private isoData = setIsoData<SearchData>(this.context);
   searchInput = createRef<HTMLInputElement>();
@@ -268,6 +270,10 @@ export class Search extends Component<SearchRouteProps, SearchState> {
     isIsomorphic: false,
   };
 
+  loadingSettled() {
+    return resourcesSettled([this.state.searchRes]);
+  }
+
   constructor(props: SearchRouteProps, context: any) {
     super(props, context);
 
@@ -323,7 +329,9 @@ export class Search extends Component<SearchRouteProps, SearchState> {
   }
 
   async componentDidMount() {
-    this.searchInput.current?.select();
+    if (this.props.history.action !== "POP") {
+      this.searchInput.current?.select();
+    }
 
     if (!this.state.isIsomorphic) {
       this.setState({
@@ -397,10 +405,6 @@ export class Search extends Component<SearchRouteProps, SearchState> {
     }
   }
 
-  componentWillUnmount() {
-    saveScrollPosition(this.context);
-  }
-
   static async fetchInitialData({
     headers,
     query: {
@@ -991,8 +995,6 @@ export class Search extends Component<SearchRouteProps, SearchState> {
           limit: fetchLimit,
         }),
       });
-      window.scrollTo(0, 0);
-      restoreScrollPosition(this.context);
 
       if (myAuth()) {
         this.setState({ resolveObjectRes: LOADING_REQUEST });

src/shared/tippy.ts

@@ -1,19 +1,55 @@
-import { isBrowser } from "@utils/browser";
-import tippy from "tippy.js";
+import { RefObject } from "inferno";
+import {
+  DelegateInstance as TippyDelegateInstance,
+  Props as TippyProps,
+  Instance as TippyInstance,
+  delegate as tippyDelegate,
+} from "tippy.js";
 
-export let tippyInstance: any;
+let instance: TippyDelegateInstance<TippyProps> | undefined;
+const tippySelector = "[data-tippy-content]";
+const shownInstances: Set<TippyInstance<TippyProps>> = new Set();
 
-if (isBrowser()) {
-  tippyInstance = tippy("[data-tippy-content]");
-}
+const tippyDelegateOptions: Partial<TippyProps> & { target: string } = {
+  delay: [500, 0],
+  // Display on "long press"
+  touch: ["hold", 500],
+  target: tippySelector,
+  onShow(i: TippyInstance<TippyProps>) {
+    shownInstances.add(i);
+  },
+  onHidden(i: TippyInstance<TippyProps>) {
+    shownInstances.delete(i);
+  },
+};
 
-export function setupTippy() {
-  if (isBrowser()) {
-    tippyInstance.forEach((e: any) => e.destroy());
-    tippyInstance = tippy("[data-tippy-content]", {
-      delay: [500, 0],
-      // Display on "long press"
-      touch: ["hold", 500],
-    });
+export function setupTippy(root: RefObject<Element>) {
+  if (!instance && root.current) {
+    instance = tippyDelegate(root.current, tippyDelegateOptions);
   }
 }
+
+let requested = false;
+export function cleanupTippy() {
+  if (requested) {
+    return;
+  }
+  requested = true;
+  queueMicrotask(() => {
+    requested = false;
+    if (shownInstances.size) {
+      // Avoid randomly closing tooltips.
+      return;
+    }
+    // delegate from tippy.js creates tippy instances when needed, but only
+    // destroys them when the delegate instance is destroyed.
+    const current = instance?.reference ?? null;
+    destroyTippy();
+    setupTippy({ current });
+  });
+}
+
+export function destroyTippy() {
+  instance?.destroy();
+  instance = undefined;
+}

src/shared/utils/browser/index.ts

@@ -3,13 +3,13 @@ import clearAuthCookie from "./clear-auth-cookie";
 import dataBsTheme from "./data-bs-theme";
 import isBrowser from "./is-browser";
 import isDark from "./is-dark";
+import nextUserAction from "./next-user-action";
 import platform from "./platform";
 import refreshTheme from "./refresh-theme";
-import restoreScrollPosition from "./restore-scroll-position";
-import saveScrollPosition from "./save-scroll-position";
 import setAuthCookie from "./set-auth-cookie";
 import setThemeOverride from "./set-theme-override";
 import share from "./share";
+import snapToTop from "./snap-to-top";
 
 export {
   canShare,
@@ -17,11 +17,11 @@ export {
   dataBsTheme,
   isBrowser,
   isDark,
+  nextUserAction,
   platform,
   refreshTheme,
-  restoreScrollPosition,
-  saveScrollPosition,
   setAuthCookie,
   setThemeOverride,
   share,
+  snapToTop,
 };

src/shared/utils/browser/next-user-action.ts

@@ -0,0 +1,46 @@
+const eventTypes = ["mousedown", "keydown", "touchstart", "touchmove", "wheel"];
+
+const scrollThreshold = 2;
+
+type Continue = boolean | void;
+
+export default function nextUserAction(cb: (e: Event) => Continue) {
+  const eventTarget = window.document.body;
+
+  let cleanup: (() => void) | undefined = () => {
+    cleanup = undefined;
+    eventTypes.forEach(ev => {
+      eventTarget.removeEventListener(ev, listener);
+    });
+    window.removeEventListener("scroll", scrollListener);
+  };
+
+  const listener = (e: Event) => {
+    if (!cb(e)) {
+      cleanup?.();
+    }
+  };
+  eventTypes.forEach(ev => {
+    eventTarget.addEventListener(ev, listener);
+  });
+
+  let remaining = scrollThreshold;
+  const scrollListener = (e: Event) => {
+    // This only has to cover the scrollbars. The problem is that scroll events
+    // are also fired when the document height shrinks below the current bottom
+    // edge of the window.
+    remaining--;
+    if (remaining < 0) {
+      if (!cb(e)) {
+        cleanup?.();
+      } else {
+        remaining = scrollThreshold;
+      }
+    }
+  };
+  window.addEventListener("scroll", scrollListener);
+
+  return () => {
+    cleanup?.();
+  };
+}

src/shared/utils/browser/restore-scroll-position.ts

@@ -1,6 +0,0 @@
-export default function restoreScrollPosition(context: any) {
-  const path: string = context.router.route.location.pathname;
-  const y = Number(sessionStorage.getItem(`scrollPosition_${path}`));
-
-  window.scrollTo(0, y);
-}

src/shared/utils/browser/save-scroll-position.ts

@@ -1,6 +0,0 @@
-export default function saveScrollPosition(context: any) {
-  const path: string = context.router.route.location.pathname;
-  const y = window.scrollY;
-
-  sessionStorage.setItem(`scrollPosition_${path}`, y.toString());
-}

src/shared/utils/browser/snap-to-top.ts

@@ -0,0 +1,3 @@
+export default function snapToTop() {
+  window.scrollTo({ left: 0, top: 0, behavior: "instant" });
+}

src/shared/utils/helpers/index.ts

@@ -17,6 +17,7 @@ import isCakeDay from "./is-cake-day";
 import numToSI from "./num-to-si";
 import poll from "./poll";
 import randomStr from "./random-str";
+import resourcesSettled from "./resources-settled";
 import sleep from "./sleep";
 import validEmail from "./valid-email";
 import validInstanceTLD from "./valid-instance-tld";
@@ -45,6 +46,7 @@ export {
   numToSI,
   poll,
   randomStr,
+  resourcesSettled,
   sleep,
   validEmail,
   validInstanceTLD,

src/shared/utils/helpers/resources-settled.ts

@@ -0,0 +1,5 @@
+import { RequestState } from "../../services/HttpService";
+
+export default function resourcesSettled(resources: RequestState<any>[]) {
+  return resources.every(r => r.state === "success" || r.state === "failed");
+}

tsconfig.json

@@ -16,7 +16,7 @@
     "skipLibCheck": true,
     "noUnusedParameters": true,
     "noImplicitReturns": true,
-    "experimentalDecorators": true,
+    "experimentalDecorators": true, // false for non-legacy decorators
     "strictNullChecks": true,
     "noFallthroughCasesInSwitch": true,
     "paths": {