Add icon to ribbon?

Can the Tabbed (aka ‘ribbon’) interface in LO Writer be customized? I want to add an extension icon to it.

LO 8.3x, Win 11, all software up to date.

No.
You can display the menu by clicking the menubar icon at the top left (tooltip Menubar). Maybe the extension entry was also added to a menu.

I added the extension icon (ReadText) to the standard toolbar myself via customization. Worked fine. That customization isn’t available for the Tabbed/ribbon. I guess I’ll just stick to the regular interface.
Thanks!