Getting favicons without hitting the network

Kris Maglione kmaglione at
Sun Oct 1 03:47:45 UTC 2017

There's a bug for this (, but it's 
pretty low priority at the moment. So the likelihood of it being 
fixed any time soon is pretty low, unless someone contributes a 


On Sun, Oct 01, 2017 at 10:57:02AM +0900, Mike Hommey wrote:
>I finally converted my tabstats addon to webextensions (mostly), but had
>to remove its use of xul:image.
>Why was it using xul:image, will you ask. Well, because xul:image has
>the attribute validate="never", which allows to use the image in the
>cache and never hit the network if it's missing. Which worked great to
>get favicons.
>It's very much undesirable for an addon that just lists tabs to be doing
>actual network requests in order to display favicons, so I removed
>favicons altogether rather than switch to img.
>Now the question is, is there any other way I can get the favicons
>without hitting the network?
>PS: another reason not to want to hit the network: some of the sites I
>have in my tabs list, and that in unloaded tabs, have no favicon and are
>behind HTTP authentication, and hitting the network triggers HTTP auth

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