I don't know where to report this issue but it keeps bothering me.
The file manager is having some problem while editing/copying/deleting files (either from a otg device or local files on the internal storage). It always got "Files has stop" and something like that.
Sometimes it hang on the middle of copying file process. The file isn't copied and the notification progress bar not moving anymore.
Sometimes it works fine, sometimes it really sucks.
I try to copy file 1 by 1, and it kinda work (sometimes it breaks too)
It might be issue from the lineage os, and I hope the dev can tell lineage to check it (I don't really sure where it begin behaving like this. Might be from the last update too, because before the last update, the file explorer works fine..)
And now I tried the es file explorer, it works fine even on background (note, I have turn off battery optimization for the stock file manager and it doesn't solve the problem...)