Many <button> elements submit a form containing the designer

[rhurling]

Is your feature request related to a problem? Please describe.

It's the same problem as #280, but concerns all other <button> elements (for example the zoom controls currently are not usable for me, since they submit the surrounding form)

Describe the solution you'd like

The same solution as in #280 needs to be applied to all other elements (<button [...] to <button type="button" [...]).

Describe alternatives you've considered

I've tried capturing and stopping propagation of the event and forcing the type="button" attribute on all <button> elements after rendering, but that doesn't work reliably.

Additional context

No response