Context menu item

It would be cool if, when the master password is available from memory or disk, there was a context menu item you could use to directly fill a password in a web site's password field.

I've been playing around trying to do this a little but I'm new to WebExtensions and struggling. Adding a context menu item and replacing the active form field with some arbitrary text is easy. But I'm struggling to include the logic needed to do real password generation, because both _background.js_ and a content script seem unable to use _require()_ calls, at least in Firefox.

I'm therefore struggling to see how I can get the logic we need into the code this menu item executes, without copying the code of every library needed to make it work. Any ideas welcome!