@kaia if you bulk rename
prename (or rename if your distro is not dumb and uses the more powerful (I wish that's what p stood for, it's Perl so better) rename out there)
or rename-utils and you get qmv which lets you open your editor and you get the old filename and the new one separated so you can individually modify the file names in the 2nd column
I used that to quickly rename all names in a directory recursively to uppercase