This is barely working proof of concept that just confirms it's possible to use TinyMCE in Zammad using either browser console or TamperMonkey user scripts.
It was created with some help from the awemsome Kagi Assistant / Claude 3.7 Sonnet (never wrote/used user scripts in browsers or the TinyMCE itself, didn't write Javascript for a decade). Developed mostly in Firefox's browser console before finally wrapping it up in TamperMonkey script.
It adds 3 custom shortcuts:
// Register keyboard shortcuts
editor.shortcuts.add('alt+m', 'Monospace', toggleMonospace);