> Um, no. "Regular" extensions used XUL They can use HTML and Javascript, same as Firefox' internals; > XUL is mostly gone ... but the UI capabilities stay t

> Um, no. "Regular" extensions used XUL They can use HTML and Javascript, same as Firefox' internals; > XUL is mostly gone ... but the UI capabilities stay the same. It's just like that for extensions. > Now the content is in its own process, the extension is in a sandbox, and the only code you can screw up with search & replace is your own extension's. That approach is the whole problem: The view of extension code as somehow inferior to Firefox' own code. Those are both applications, not the code from some website run inadvertently when you visit a web page, but something you installed because you wanted to have run. > some aren't implemented Everything is implemented - inside FF. It's just arbitrarily being kept inaccessible to extensions. Note that, in Thunderbird, a small hole-in-the-wall has been implemeneted, for loading regular extensions, and they are able to run with full privileges and do the work they need to be doing.