Validator Gone Wild?

I really must be doing something wrong. Has anyone noticed a strange space expanding to the bottom of fields in a form as you tab to each field? Or when you click the submit button? It can be subtle at times, but it definitely happens. Some file failing to update on the server perhaps?

However, when I remove the validator from form and their respective links in the HEAD, the movement stops.

See the attached video below.

Recording.mp4 (4.1 MB)

The problem, I believe was the Bootstrap 3. Once I changed the page to Bootstrap 4, it seems to have locked the fields. Now they don’t move.