RCNConfigRealtime trying to connect while in background

[plu]

Description

In [RCNConfigRealtime retryHTTPConnection] there's some early return:

// Retry mechanism for HTTP connections
- (void)retryHTTPConnection {
  __weak RCNConfigRealtime *weakSelf = self;
  dispatch_async(_realtimeLockQueue, ^{
    __strong RCNConfigRealtime *strongSelf = weakSelf;
    if (!strongSelf || strongSelf->_isInBackground) {
      return;
    }

This doesn't seem to work reliably. We have millions of non-fatals on Crashlytics that run into FIRRemoteConfigUpdateErrorStreamError and 99% of them report that the app is in background.

Reproducing the issue

Unfortunately we don't have any steps on how to reproduce this, but in the screenshot above you can see that it happens very often on production.

Firebase SDK Version

12.7.0

Xcode Version

26.2

Installation Method

Swift Package Manager

Firebase Product(s)

Remote Config

Targeted Platforms

iOS

Relevant Log Output

Non-fatal: Error
Domain: com.google.remoteconfig.update.ErrorDomain Code: 8001 NSLocalizedDescription: Unable to connect to the server. Check your connection and try again.

If using Swift Package Manager, the project's Package.resolved

Expand Package.resolved snippet

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}

If using CocoaPods, the project's Podfile.lock

Expand Podfile.lock snippet

Replace this line with the contents of your Podfile.lock!

[plu]

In the documentation of UIApplicationWillEnterForegroundNotification Apple writes:

A notification that posts shortly before an app leaves the background state on its way to becoming the active app.

This could explain why beginRealtimeStream is sometimes called while still being in background.

Does it make sense to switch to UIApplicationDidBecomeActiveNotification instead?

 - (void)backgroundChangeListener {
   [_notificationCenter addObserver:self
                           selector:@selector(isInForeground)
-                              name:@"UIApplicationWillEnterForegroundNotification"
+                              name:@"UIApplicationDidBecomeActiveNotification"
                             object:nil];

[plu]

@paulb777 sorry to tag you directly, any chance your team could have a look into this, please?