Fix spurious session corruption error

src/stores/LifecycleStore.ts

@@ -16,6 +16,7 @@ limitations under the License.
 
 import { SyncState } from "matrix-js-sdk/src/matrix";
 import { MINIMUM_MATRIX_VERSION, SUPPORTED_MATRIX_VERSIONS } from "matrix-js-sdk/src/version-support";
+import { logger } from "matrix-js-sdk/src/logger";
 
 import { Action } from "../dispatcher/actions";
 import dis from "../dispatcher/dispatcher";
@@ -61,6 +62,7 @@ class LifecycleStore extends AsyncStore<IState> {
             case "MatrixActions.sync": {
                 if (payload.state === SyncState.Syncing && payload.prevState !== SyncState.Syncing) {
                     // We've reconnected to the server: update server version support
+                    // This is async but we don't care about the result, so just fire & forget.
                     checkServerVersions();
                 }
 
@@ -84,37 +86,46 @@ class LifecycleStore extends AsyncStore<IState> {
 }
 
 async function checkServerVersions(): Promise<void> {
-    const client = MatrixClientPeg.get();
-    if (!client) return;
-    for (const version of SUPPORTED_MATRIX_VERSIONS) {
-        // Check if the server supports this spec version. (`isVersionSupported` caches the response, so this loop will
-        // only make a single HTTP request).
-        // Note that although we do this on a reconnect, we cache the server's versions in memory
-        // indefinitely, so it will only ever trigger the toast on the first connection after a fresh
-        // restart of the client.
-        if (await client.isVersionSupported(version)) {
-            // we found a compatible spec version
-            return;
+    try {
+        const client = MatrixClientPeg.get();
+        if (!client) return;
+        for (const version of SUPPORTED_MATRIX_VERSIONS) {
+            // Check if the server supports this spec version. (`isVersionSupported` caches the response, so this loop will
+            // only make a single HTTP request).
+            // Note that although we do this on a reconnect, we cache the server's versions in memory
+            // indefinitely, so it will only ever trigger the toast on the first connection after a fresh
+            // restart of the client (which has just happened since it's started syncing, so this should
+            // never actually cause a request).)
+            if (await client.isVersionSupported(version)) {
+                // we found a compatible spec version
+                return;
+            }
         }
-    }
 
-    const toastKey = "LEGACY_SERVER";
-    ToastStore.sharedInstance().addOrReplaceToast({
-        key: toastKey,
-        title: _t("unsupported_server_title"),
-        props: {
-            description: _t("unsupported_server_description", {
-                version: MINIMUM_MATRIX_VERSION,
-                brand: SdkConfig.get().brand,
-            }),
-            acceptLabel: _t("action|ok"),
-            onAccept: () => {
-                ToastStore.sharedInstance().dismissToast(toastKey);
+        // This is retrospective doc having debated about the exactyl what this toast is for, but
+        // our guess is that it's a nudge to update, or ask your HS admin to update your Homeserver
+        // after a new version of Element has come out, in a way that doesn't lock you out of all
+        // your messages.
+        const toastKey = "LEGACY_SERVER";
+        ToastStore.sharedInstance().addOrReplaceToast({
+            key: toastKey,
+            title: _t("unsupported_server_title"),
+            props: {
+                description: _t("unsupported_server_description", {
+                    version: MINIMUM_MATRIX_VERSION,
+                    brand: SdkConfig.get().brand,
+                }),
+                acceptLabel: _t("action|ok"),
+                onAccept: () => {
+                    ToastStore.sharedInstance().dismissToast(toastKey);
+                },
             },
-        },
-        component: GenericToast,
-        priority: 98,
-    });
+            component: GenericToast,
+            priority: 98,
+        });
+    } catch (e) {
+        logger.warn("Failed to check server versions", e);
+    }
 }
 
 let singletonLifecycleStore: LifecycleStore | null = null;