"Migrate installation" deleted my files

[ilia-21]

I had my game installed in ~/mnt/HDD/(game name). (so the exe location is ~/mnt/HDD/(game name)/(game name).exe) It was installed there by the official launcher, so when I got sleepy launcher I selected it as my game folder in "Global game installation folder". I clicked "launch" and it said that game resources are not found. Okay, maybe I need to selected a folder, which contains (game name) folder, not (game name) folder, so I went ahead and selected ~/mnt/HDD Game files still not found. When I checked my ~/mnt/HDD folder, there was nothing but game files. My projects folder that was ~/mnt/HDD/Projects is gone. I instantly unmounted this partition.
Is this intended behavior? If so, why isn't there a warning that migrating installation will delete files?
There's also for some reason was a folder named "(game name) Game" which contained another folder with the same, in that folder there was another folder with that exact name. I believe I went 50 folders deep, it was still going. I was not a symlink, it was actual folder (confirmed via ls -l)

[elfennani]

Same happened with me a few months ago with honkers railway launcher, thankfully it deleted only Documents directory which had only some games in it. It was frightening seeing a sudden rise in free storage.

[ilia-21]

Update: I found my folders, but they're empty, they were in that folder that had itself inside 100 times.

❯ pwd
/home/ilia21/mnt/HDD/ZZZ/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game/(game name) Game
❯ ls
 Documents
󰉍 Downloads
 Games
 Projects
 SteamLibrary
 '(game name) Game'

EDIT: Dolphin shows folders as empty, terminal shows files there, I guess this is because of long pathname