editor.ui.registry.addButton() since version 5.1

[migliori]

Hi,

Until now I was calling editor.ui.registry.addButton() from editor.on('init') callback in my Tinymce Bootstrap plugin

The V5.1 broke this, now editor.ui.registry.addButton() MUST be called on Setup

Maybe this could be mentioned in the documentation changelog?

[lnewson]

Hi @migliori, this wasn't something intentional, as it should really never have worked when adding buttons on init. This is because the buttons need to be added before the UI is rendered, which happens before the init event is fired. Additionally, all of our documentation examples show it should be done in setup instead of on init, so we don't believe this needs to be mentioned.

[migliori]

Thank you for your answer; indeed it makes sense to build the UI before initializing