gThumb 3.12.2-1 is showing thumbnails in the correct EXIF orientation, however gThumb is not playing the videos in the correct EXIF rotation position, when it comes to videos that are taller that they are wide (portrait). Obviously your EXIF rotation code for the thumbnails could be used to rotate videos that are playable.
When using Files (nautilus) 42.1.1-1 it should be easier to copy the address from the file explorer address bar (or whatever it’s called). You can
Open in Terminal, after right clicking on the three dots but you should also be able to copy the address with ease.
I can’t seem to reproduce the problem, but after opening multiple activities, for some reason the icons in the Applications window grew in size. It just happened about a half hour ago. It’s happened before, as well. Sorry I can’t be more help on the last issue. I’ll get back to you if I figure it out. It is happening on occasion, though.