Steps to reproduce the issue

Edit a Mail Template in Joomla 4 admin

Change the language code manually in the URL

Eg

http://example.com/administrator/index.php?option=com_mails&view=template&layout=edit&template_id=plg_user_joomla.mail&language=en-GBfrerferferferferf

Click save

Expected result

Input validation on the language code before it gets anywhere near a mysql query

Actual result

Save failed with the following error: Data too long for column 'language' at row 1

Additional Information

If you use &language=A the mail template saves - this also should be stopped, as A is not a valid input for language code! And this is persisted to the database!