Borderlands Save Game Location
Windows
Borderlands save games can be found here:
C:\Users\[user_name]\Documents\My Games\Borderlands\SaveData\
Linux
Linux (Proton):
~/.steam/steam/userdata/[user_id]/8980
Borderlands save games can be found here:
C:\Users\[user_name]\Documents\My Games\Borderlands\SaveData\
Linux (Proton):
~/.steam/steam/userdata/[user_id]/8980