Andy Spix

Seeing the same issue, appears to be Firefox-Mac specific: Safari 14 - works as expected Chrome 91 - works as expected Firefox 89 - posts after click in any checkbox...

I'm not 100% clear on all of the mechanisms involved, but it appears that a submit event is generated from the button elements used to construct the dropdown after it...

It is interesting that neither Chrome or Safari show the same behavior with the checkbox buttons (all three browsers show type='submit' when inspected). I suspect Mac support (or lack thereof)...