Bring back option to separate sessions/credentials in tree view

I just accidentally disabled "unmerge session/credentials in tree view". Now we cant re-enable it because its gone. Turns out this was removed a while ago I just learned.

Please! bring back the option to unmerge sessions/credentials.
This is a huge pain for us, we have 10k+ entries in several vaults and have built everything according to this structure.
Moving everything to subfolders is just not feasible and is no solution aswell when working with tree view.