[gdeglin]

We've tried contacting OEMs about some of the more buggy behaviors we've seen related to their power optimization features. Unsurprisingly, even when we did get ahold of someone in the US who was senior enough to understand the problem, they had limited ability to influence the China-based operations of the company. Getting whitelisted seems nearly impossible unless you are a large company with a major presence in China and connections to the OEMs.

Google has hinted that they are working on something to improve the situation, but it's been years without resolution and the problem appears to have become worse instead of better.

There's a lengthy thread in this old Android bug report about the issue https://issuetracker.google.com/issues/122098785

[tdrp]

Thanks for the link. I noticed some of these OEMs had started implementing their own "more reliable" PushKits, but I am guessing that the privacy implications are quite bad so it's basically a non-starter.

[gdeglin]

Yes. Also, for example, Huawei is not permitted to use Google Services on their new devices. As a result, they leverage a replacement called HMS and they replaced FCM with the HMS "Push Kit".

Privacy or not, it's the only way to send notifications to new Huawei devices that don't have FCM like the Huawei P40 that are sold worldwide. This isn't a niche issue -- Huawei was recently the #1 manufacturer of smartphones outside of China, surpassing both Apple and Samsung. Although this ranking has fallen as consumers have become aware of the lack of Google Services on these devices.