MC Java Launcher - login not persistent

Using a non-migrated Mojang account, the minecraft launcher fails to remember the user password upon launch, even if the "keep me logged in" checkbox is ticked. For reference I am using the minecraft-launcher package from the Arch Linux AUR, installed using the yay helper under the ~/.minecraft directory.
Attached is the terminal output when running minecraft-launcher. I have tried reinstalling the package and deleting/rebuilding all associated .json files, to no avail. No abnormalities are apparent in the launcher_accounts.json file, with "persistent" : true, as it should be, and a blank "userproperties" array. All other variables contain hex keys/hashes as normal.
Possibly combine/replace MCL-18924, which seems similar, asides from "AccessToken" not being empty in my case.