

Not all notifications go through FCM but all push notifications do as far as I’m aware - which is what the previous comment and the post title are talking about.
It is, in fact, worrying for privacy implications on the one hand and a real monopolizing factor on the other since if you wish to deliver an app which needs to implement such notifications you’re using Google’s service or constantly drain the user’s battery.
There’s UnifiedPush which tries to provide an open alternative but so far unfortunately still sees very little adoption.
The terminal-based file browser space is so filled today but for my part I love what vifm has done for the dual-pane midnight commander concept - it’s the same basic idea, uses (somewhat) vim-like bindings by default and is super extensible.