Any GUI Linux directory comparison tools that work?

I tried KDIFF3, it crashes partway through comparison. I understand that v1.10 has a bug and crashes when a directory has symlinks in it, as my home folder does.

I tried KDIFF3 v1.12 via the abomination called Flatpak, but it also crashes partway through scanning.

I tried MELD, it just hangs there "scanning" but uses no CPU and is doing nothing...

Ideas?

#Linux

@dancingtreefrog

I usually use Meld, but yeah, I've seen it crash and burn sometimes. Not sure what would be better. If anybody has any ideas, I'd like to hear them!

@argv_minus_one I can't figure out how to do anything with Meld. Pick the two folders, it just hangs doing nothing... Ideas?
@dancingtreefrog @argv_minus_one How much data?
Any filters set?
Comparing hashes for all files in a big data set can take a while...
@aldarch3 @argv_minus_one Filters? I assume you're referring to Meld? I've never set or changed any filters in it, don't know how to do that, anyway.
@dancingtreefrog @argv_minus_one
I'd imagine that taking a while.
Not in front of it, but poke around in the settings - I think you can set it to just compare size/date and not contents.
Graphical user interface — rmlint (2.10.3 Ludicrous Lemur) documentation

@aldarch3 @argv_minus_one Hmm, interesting. Kind of like a GUI tool I already have, CZKawka's fork of fslint... Except I'm not looking for file duplicates between the directories, I'm looking for files that exist only in one of them.