(cc and reply-to maildev, as these are technical questions) Jörg Knobloch wrote on 20.11.17 23:02: > when it come to digging around in M-C internals like the add-ons > manager, we have very little knowledge, unless you want to volunteer. > > ... I'd still have no knowledge about that add-on stuff, so it would > be a lot of trial and error and begging people for help. While the addons manager code is surely not pretty, neither is mail/ code. It's XUL/HTML and JS. DOM Inspector and the JS Debugger gets you a long way here. Take a Firefox before the change, which still had the options button, pick it with DOM Inspector, and follow the call stack what happens when you click it. It might call some XPCOM, but you can follow the code the same. On the other side, you have the documentation of how a XUL extension exposes (exposed) its Options page. You just have to add a button that calls that API, whatever it is. I know I'm a bit hand-waving, but that's what XUL extension authors did all day long. It's not hard. They only cook with water, as the German proverb says.