The decision / condition of showing sidebar permanently on tablet?

I have two Android tablets (Both installed Amaze file manager 3.3.4, via Google Play):

1. [left] ASUS ZenPad 3s 10 (P027), resolution = (1536, 2048), width / height ratio = 0.75
2. [right] Sansumg Galaxy Tab S6 (SM-T860), resolution = (1600, 2560), width / height ratio = 0.625

The previous one (ZenPad) has smaller resolution, but can always show the sidebar permantely; while the later one has larger resolution, but can't show like that, very inconvenient for a tablet:

BTW, the behavior of mouse right clicking on file should be showing the menu of it instead of back to last page, I think.