The DB update script /install/update.php currently has two tasks: (1) update the database scheme to a new version, and (2) insert new preferences into the database, if the admidio codebase added a new preference.
However, the script currently checks only for a required DB update and does not do anything if no DB update is required. In particular during code development, one sometimes adds a new preference, but does not need a DB update. In that case, the update script will NOT inser the new preference into the database.
The update script should also check for added preferences and insert them, even if no DB update code needs to run.