Jérôme Gamez

Thank you for providing me with the information! HTTP/2 support has been available since version 7.47 (which was released in 2016). I believe that should indeed be the issue. However,...

7.9 would continue to work after June 30th - it already uses the new endpoints, but calls them synchronously instead of asynchronously since 7.10 (for better performance). I could implement...

~~It came to me (in the shower of all places 😅) that perhaps I can make it work with a small change, I remember adding something some time back that...

Could you please test with https://github.com/kreait/firebase-php/pull/903 if this solves the issue?

Hm, if the constants are set, HTTP/2 is supported by your environment, and this isn't the solution. Are you using a proxy?

For the time being, staying on 7.9 seems to be the best option, and it has no bugs or missing features, so you should be good for the foreseeable future....

HTTP/2 is needed to make sending FCM messages for several thousand, sometimes even 100K+ messages, high-performant. It'a a feature that even the official [Admin Node SDK](https://github.com/firebase/firebase-admin-node/issues/2488) currently lacks (there's [an...

The change in the PR alone didn't help, that was the problem with the PR :/

But if it works for you, I'll happily re-add the check in another PR - it's not as if I hadn't tried 😅

#903 doesn't seem to have worked (https://github.com/kreait/firebase-php/issues/888#issuecomment-2144293337). Worse, if it works for you but not @Daniel-Cong, I'm even more inclined to not check this, who knows what else is at...