Note:
If I'm not mistaken, the class "should be" the same for all fieldsets. I did not remove the group to keep it bc.
Furthermore I've reformatted some code blocks to match the code sniffer rules and added a more strict check to the legend rendering method of each fieldset.
Background:
If one overrides a translatable string with an empty string, the legend tag would be rendered without a text which could lead to a messed up styling of the form in general.
I have tested this item successfully on 9db9d13
This comment was created with the J!Tracker Application at issues.joomla.org/joomla-cms/8387.