Merge pull request #3526 from deltachat/adb/issue-3525

use synchronized block to avoid IllegalMonitorStateException

.github/workflows/preview-apk.yml

@@ -49,7 +49,7 @@ jobs:
         run: ./gradlew --no-daemon assembleGplayDebug
 
       - name: Upload APK
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: app-preview.apk
           path: 'build/outputs/apk/gplay/debug/*.apk'

src/main/java/org/thoughtcrime/securesms/service/FetchForegroundService.java

@@ -49,6 +49,7 @@ public final class FetchForegroundService extends Service {
         // The background fetch was successful, but we need to wait until all events were processed.
         // After all events were processed, we will get DC_EVENT_ACCOUNTS_BACKGROUND_FETCH_DONE,
         // and stop() will be called.
+        synchronized (STOP_NOTIFIER) {
           while (fetchingSynchronously) {
             try {
               // The `wait()` needs to be enclosed in a while loop because there may be
@@ -59,12 +60,15 @@ public final class FetchForegroundService extends Service {
         }
       }
     }
+  }
 
   public static void stop(Context context) {
     if (fetchingSynchronously) {
       fetchingSynchronously = false;
+      synchronized (STOP_NOTIFIER) {
         STOP_NOTIFIER.notifyAll();
       }
+    }
 
     synchronized (SERVICE_LOCK) {
       if (service != null) {