Capture click events on selected if not all toolbar button

Question

Toolbar buttons like: Insert/edit link, Insert/edit images, Insert/edit media, Insert templates and Source code

I already tried the

editor.on("ExecCommand", function(e) { // checking of e.command });

Only the first Insert/edit link works as I have a code that inserts a custom button right beside the URL button.

tinymce 6.7.0

Expected to insert a custom code on the click events on the tinymce toolbar buttons.