See screenshot.

The url of the <img> element seems wrong, has a bunch of nested protocols:

moz-anno:favicon:moz-anno:favicon:moz-anno:favicon:moz-anno:favicon:https://github.com/fluidicon.png"

If I leave this as moz-anno:favicon:https://github.com/fluidicon.png then it uses the right image.

I can't repro this on a clean profile, maybe it comes from here? Marco, do you know what might be going on?

If tab.icon is already a moz-anno:favicon, GetFaviconLinkForIcon should not really add another prefix, same for getIconForUrl... That's a simple fix and I will just do that.

I think it is being added multiple times because remote tabs are cached, and every time we go through the list we add a moz-anno:favicon to tab.icon... that doesn't make sense.

Thank you for finding this.

https://hg.mozilla.org/mozilla-central/rev/094d4087bf81

I tried to reproduce this issue but I was unsuccessful. Would it be possible to have reproduction steps in order to properly verify this issue?
Thank you.

I couldn't repro on a clean profile, so unfortunately no concrete STR. Daisuke maybe you know?

I suspect you need a tab synced from another desktop device

Hello!
Yes, as Marco said, I could reproduce it with remote tabs in my env.

STRs:

1. Launch Firefox Release (116.0.2).
2. Login to Firefox account in Release.
3. Input git on the urlbar in Release, and confirm that there are no suggestions for any remote tabs.
4. Launch Firefox Nightly (118.0a1).
5. Login to Firefox account in Nightly, and confirm that the opening tabs will be shared in Sync Settings.
6. Open https://github.com in Nightly.
7. Sync Firefox account in Nightly (Click Sync now).
8. Sync Firefox account in Release (Click Sync now).
9. Input git on the urlbar in Release, and confirm there is the suggestion for github.com that is opening in Nightly.

Then, confirm the url of the icon of the suggestion using Browser Toolbox in Release.
(To confirm will be easier if set ui.popup.disable_autohide to keep the urlbar result)
I attached the screenshot. (Sorry, Japanese!)