Create a Content Language. You can save an incorrectly formatted Language Tag, i.e. a tag which does not obey to the simple rule: 2 or 3 lowercase letters + dash + 2 Uppercase letters
Example: fr-FR, ckb-IQ, etc.
The field accepts anything....
This patch throws an error when the format is wrong.
After applying, try to save anything different from the rule above.
test
works good,
now I do not able to save
blabla