Firefox can't handle downloads with addons

I’ve created a bug on bugzilla. I have flareget installed and firefox can’t handle downloads using flatget addon.
It works perfectly on deb app


Thanks for the bug report @Alculete. Let’s continue this conversation there.

OK, thank you @oSoMoN. One other thing I noticed it seems xdg-open is not working also tested on to install an app. It also works on deb

Indeed, opening the software store GUI from the firefox snap doesn’t work. I’m not seeing any output, but the same problem can be observed with the chromium snap, and there I see the following:

user-open error: Supplied URL scheme "snap" is not allowed

And indeed, the only schemes currently whitelisted are http, https and mailto:

$ grep -n allowedURLSchemes userd/launcher.go
56:	allowedURLSchemes = []string{"http", "https", "mailto"}
96:	if !strutil.ListContains(allowedURLSchemes, u.Scheme) {

@mvo, @jdstrand: has the snap scheme been considered for addition to that whitelist? Perhaps there are security implications to allowing a confined app to suggest the user install another (potentially malicious) snap by popping open the software store GUI ?

This is

So long as the URL opens the software store and the information in the link software store clearly shows all relevant details for the snap so the user can make an informed decision to install or not, I don’t think there are any security implications in this.

A web page can already could just as easily use an http/https link to a store URL or to some other page. Properly supporting snap:// would improve upon that in the normal case.

Thanks for the analysis @jdstrand. I’m not familiar with the snapd codebase, is it just a matter of adding “snap” to the scheme whitelist (and update the corresponding unit tests), or is there more to it?

Now that the snap urls have been re-enabled in the store, it makes sense that our own snapd to be able to deal with them.


Pull request up for review.

Will this solve also solve the addon problem reported first?

No, this won’t solve your problem with flareget.

@oSoMoN I’m not sure if this is happening only to me but snap links still not working on firefox only, on chromium

I’m seeing the same thing. This is because firefox doesn’t delegate to xdg-open, instead it queries the system to know which application is associated to the snap:// protocol, and it tries to run it directly, which fails because of confinement. I have commented on the upstream bug report and asked to re-open it.

things that still not working on firefox snap

  • Unable to use Open with… on another snap (tested with vuze-vs) works well on deb version;
  • Unable to use download managers (tested with flareget and JDownloader)
  • Old cursor icon style;
    This are the things I noticed. Will update if something comes up
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