Permit extensions to run on new tab page

[alperenbabagil]

We should be able to let some extensions work on native pages like the new tab page. I use a mouse gesture extension and I can't close the new tab with a gesture.

[Jon]

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[mconnor]

The short reason for why WebExtensions can’t access new tab is that it would create a major security risk.  The New Tab page is privileged browser code, not web content, so giving an extension access to that page would completely bypass the extension security model and give the extension full access to all of Firefox.

Unfortunately, access in the WebExtension model is pretty binary: you can inject scripts or you can’t.  We’d have to create something fairly different to allow “safe” access to New Tab (and/or other in-content pages) for something like mouse gestures.  To give an example of what it would take to support this safely, we would need to add core support for a defined set of mouse gestures, then allow an add-on to register commands/actions for those gestures.  That’s a lot of work for a relatively niche feature, so it’s not going to happen soon, but it’s the type of approach we’re thinking about for the future.

[fenjen]

Thanks for the reply. What I really don't understand is why Firefox changed from `about:blank` to `about:newtab`. The former allows extensions to work, the latter doesn't (while not providing anything useful).

Using Mouse Gestures is a super boost in Web Browsing. I've been using it since almost 20 years. Not working Mouse Gestures on some pages is infinitely annoying. You make your gesture move to close the New Tab and what you get is a context menu 😞 This is also true for the special pages. The only consolation is that you don't use these sites so often (and - ultimately avoid them).

I assume this "feature" is for security. But now we have to install a third-party addon which is not actively monitored by Mozilla: https://addons.mozilla.org/firefox/addon/new-tab-about-blank/

Best would be to allow the Mozilla monitored plugins like Gesturefy and Foxy Gestures to access special pages. This would also prevent people from change these two, too:

extensions.webextensions.restrictedDomains
privacy.resistFingerprinting.block_mozAddonManager