diff --git a/src/client/initMatrix.ts b/src/client/initMatrix.ts
index ca33ebd39..605d0f300 100644
--- a/src/client/initMatrix.ts
+++ b/src/client/initMatrix.ts
@@ -20,9 +20,12 @@ export const IDB_VERSION_CONFLICT = 'IDB_VERSION_CONFLICT';
  * session. When that happens the device "resurrects" with a blank key store and the
  * client re-uploads a one-time key at an id Synapse already holds → a permanent
  * `400 M_UNKNOWN: … already exists` upload-conflict storm (and, downstream,
- * undecryptable to-device/media keys). `persist()` grants based on engagement / PWA
- * install and shows no prompt; denial/absence is non-fatal.
+ * undecryptable to-device/media keys). Chromium/WebKit answer `persist()` at once
+ * (engagement / PWA install); Firefox shows a permission prompt and the promise
+ * stays pending until it's answered. Denial/absence is non-fatal.
  */
+const PERSIST_WAIT_MS = 1500;
+
 export const requestPersistentStorage = async (): Promise<boolean> => {
   try {
     if (!navigator.storage?.persist) return false;
@@ -39,7 +42,15 @@ export const requestPersistentStorage = async (): Promise<boolean> => {
 
 export const initClient = async (session: Session): Promise<MatrixClient> => {
   // Protect the crypto store from eviction before we create and write to it.
-  await requestPersistentStorage();
+  // [Gitea #303] Never block startup on the answer: Firefox prompts and leaves
+  // the promise pending until the user responds, which froze the app on
+  // "Heating up". KE-1 only needs the request made; give it 1.5 s at most.
+  await Promise.race([
+    requestPersistentStorage(),
+    new Promise<boolean>((resolve) => {
+      setTimeout(() => resolve(false), PERSIST_WAIT_MS);
+    }),
+  ]);
 
   const indexedDBStore = new IndexedDBStore({
     indexedDB: globalThis.indexedDB,