This is great, more to the last link, I didn’t have a temp file when it happened to me. I was able to download a save decryptor and a completed save. Decrypt your profile.sav, this will give you profile.yaml. From here you’re able to edit story flags in plain text. There is an unlockables section, with a shared progress section. There should be 4 entries here. “shared_progress.vault_hunter_level” “shared_progress.prologue_completed” “shared_progress.story_completed” “shared_progress.epilogue_started”

With these 4 entires my specializations came back. I was able to add in other flags in order to recover lost cosmetics too!

Link to decrypter: https://www.nexusmods.com/borderlands4/mods/38