If you attempt to save a data form that checks that fields match a regular expression, and a mismatch is found, the save button appears to be non responsive. It shows the popup that the page is being saved, then stops.
Instead, the page should automatically scroll up to the first error, so that there is no doubt as to why the page did not save. The user is shown the problem that they need to fix.
An alternative would be to show a summary of all the things that need to be fixed at the top of the page above all data form fields, and then to scroll up to this summary.