After T345649 was completed, CheckUser now trims the trailing and leading spaces for uach_value on inserts into the cu_useragent_clienthints table. However, as evidenced by the data collected in T344800, some of this data is being provided with trailing and leading spaces.

In T345649 it was suggested to create a maintenance script to trim the pre-existing data. This task will track creation of a maintenance script to do this which will also be added to update.php.

Acceptance criteria

• A maintenance script that trims trailing and leading spaces from values in uach_value of the cu_useragent_clienthints table, making sure to re-assign IDs if the trimmed version already existed.
• Add this maintenance script to update.php to fix local wikis that have already been collecting data.
• Have this script be run on WMF wikis