Iframe extension thin wrapper

[louisgv]

It seems that a lot of extension has moved over into using iframe and inject them into either a content script or an offscreen document. There's a couple of benefit such as iframe update and dedupe from cws. Problem with this type of extension are:

• Message piping between iframe <-> upstream is annoying
• Doesn't work offline, won't be usable with PWA

What are some other pros/cons of iframe extension?