Do not eagerly decrypt breadcrumb rooms

Author: germain-gg

src/stores/BreadcrumbsStore.ts

@@ -16,14 +16,12 @@ limitations under the License.
 
 import SettingsStore from "../settings/SettingsStore";
 import { Room } from "matrix-js-sdk/src/models/room";
-import { EventType } from "matrix-js-sdk/src/@types/event";
 import { ActionPayload } from "../dispatcher/payloads";
 import { AsyncStoreWithClient } from "./AsyncStoreWithClient";
 import defaultDispatcher from "../dispatcher/dispatcher";
 import { arrayHasDiff } from "../utils/arrays";
 import { isNullOrUndefined } from "matrix-js-sdk/src/utils";
 import { SettingLevel } from "../settings/SettingLevel";
-import { MatrixClientPeg } from '../MatrixClientPeg';
 
 const MAX_ROOMS = 20; // arbitrary
 const AUTOJOIN_WAIT_THRESHOLD_MS = 90000; // 90s, the time we wait for an autojoined room to show up
@@ -61,30 +59,6 @@ export class BreadcrumbsStore extends AsyncStoreWithClient<IState> {
         return this.matrixClient && this.matrixClient.getVisibleRooms().length >= 20;
     }
 
-    componentDidUpdate(prevProps, prevState) {
-        const prevRoomCount = (prevState.rooms?.length || 0);
-        const currentRoomCount = (this.state.rooms?.length || 0)
-
-        // Only decrypting the breadcrumb rooms events on app initialisation
-        // when room count transitions from 0 to the number of rooms it contains
-        if (prevRoomCount === 0 && currentRoomCount > prevRoomCount) {
-            const client = MatrixClientPeg.get();
-            // Rooms in the breadcrumb have a good chance to be interacted with
-            // again by a user. Decrypting the messages ahead of time will help
-            // reduce content shift on first render
-            this.state.rooms?.forEach(async room => {
-                const [cryptoEvent] = room.currentState.getStateEvents(EventType.RoomEncryption);
-                if (cryptoEvent) {
-                    if (!client.isRoomEncrypted(room.roomId)) {
-                        // XXX: Private member access
-                        await client._crypto.onCryptoEvent(cryptoEvent);
-                    }
-                    room?.decryptAllEvents();
-                }
-            });
-        }
-    }
-
     protected async onAction(payload: ActionPayload) {
         if (!this.matrixClient) return;