fix(readAllNotificationsButton): Mark threads as read (#2437)

src/plugins/readAllNotificationsButton/index.tsx

@@ -22,14 +22,34 @@ import { addServerListElement, removeServerListElement, ServerListRenderPosition
 import ErrorBoundary from "@components/ErrorBoundary";
 import { Devs } from "@utils/constants";
 import definePlugin from "@utils/types";
+import { findStoreLazy } from "@webpack";
 import { Button, FluxDispatcher, GuildChannelStore, GuildStore, React, ReadStateStore } from "@webpack/common";
+import { Channel } from "discord-types/general";
+
+interface ThreadJoined {
+    channel: Channel;
+    joinTimestamp: number;
+}
+
+type ThreadsJoined = Record<string, ThreadJoined>;
+type ThreadsJoinedByParent = Record<string, ThreadsJoined>;
+
+interface ActiveJoinedThreadsStore {
+    getActiveJoinedThreadsForGuild(guildId: string): ThreadsJoinedByParent;
+}
+
+const ActiveJoinedThreadsStore: ActiveJoinedThreadsStore = findStoreLazy("ActiveJoinedThreadsStore");
 
 function onClick() {
     const channels: Array<any> = [];
 
     Object.values(GuildStore.getGuilds()).forEach(guild => {
-        GuildChannelStore.getChannels(guild.id).SELECTABLE
+        GuildChannelStore.getChannels(guild.id).SELECTABLE // Array<{ channel, comparator }>
-            .concat(GuildChannelStore.getChannels(guild.id).VOCAL)
+            .concat(GuildChannelStore.getChannels(guild.id).VOCAL) // Array<{ channel, comparator }>
+            .concat(
+                Object.values(ActiveJoinedThreadsStore.getActiveJoinedThreadsForGuild(guild.id))
+                    .flatMap(threadChannels => Object.values(threadChannels))
+            )
             .forEach((c: { channel: { id: string; }; }) => {
                 if (!ReadStateStore.hasUnread(c.channel.id)) return;