Running Nightly on a Samsung Galaxy S8. There's a low power saving mode, when in high saving mode, not all apps can be started or attached to the home screen. Samsung browser, chrome can be started, however Firefox can't. I don't know if it's a restriction of Firefox or the OS. But it would be nice to be able to use Firefox in that mode.
It seems that this is a hard coded list that Samsung creates. Apps are not allowed to opt into this support. If you have rooted your device then it is possible to add apps to the list. https://forum.xda-developers.com/showthread.php?t=2750393
Interesting.. Could we work with Samsung to get added to that list?