Issue #3094059 by Sam152, seanB, phenaproxima, oknate, 5n00py,...

Issue #3094059 by Sam152, seanB, phenaproxima, oknate, 5n00py, andrewmacpherson, matthieuscarset, dion-jensen: The media library widget "Add media" button incorrectly submits form handlers of forms it is embedded in

(cherry picked from commit ff4351ab)