I would really like if the add on "Open in Browser"[1] could be ported over to WebExtensions. It has about 8 thousand users. The add on is a great defense against websites that force you to download pdf files or images that could be displayed in the browser just as well. From what I saw is that its main functionality boils down to: 1. adding a XUL overlay to the "what to do with this file" menus to let the user chose to open in browser and then 2. reloading the URL, overriding the MIME type Both 1 and 2 seem to be not be possible with current Web extensions. I'll file issues for both of them. [1] Links: AMO: https://addons.mozilla.org/firefox/addon/open-in-browser/ Github: https://github.com/spasche/openinbrowser Porting tracking issue in their repo: https://github.com/spasche/openinbrowser/issues/23

This can be done with Web Extensions native messaging, but WE requires the extension developer to implement an external binary that can launch other apps, and that receives messages from the extension itself.

I'm not sure whether you have understood correctly the intentions of the add on. Its not meant to start other programs, its meant to prevent that, to display the content inside the same browser. Not to launch chrome/internet explorer, or any other external program.

(In reply to est31 from comment #2) > I'm not sure whether you have understood correctly the intentions of the add > on. Its not meant to start other programs, its meant to prevent that, to > display the content inside the same browser. Not to launch chrome/internet > explorer, or any other external program. Ah yes, sorry, I was thinking of another add-on: Open with

If there's bugs for the specific APIs (for example bug 1344648) we'll discuss those in the design decision meeting instead of a general tracking bug for porting an extension.