@all this seems to be something Android (15) specific not only affecting Fairphone, so there is not much to be done by Fairphone in this case…So FP is aware and having an eye on it, however these are deep system-level changes that Google implemented in Android 15
This isn’t unique to Fairphones. Similar issues are being reported across the Android ecosystem, even on Google’s own devices (Pixel 9 Killing Apps in Background; Pixel killing background apps ).