I was looking for something to help me organize my Firefox tabs when I find FaviconizeTab. I was trying to avoid tabs scrolling as possible but in the same time without altering tabs widths, and FaviconizeTab seems to works fine here. You can simply click on the tabs you want to iconize and width will be reduced to show the favicon only. Combination between [Ctrl,Shift,Alt] + Click or Double click on the tab can be selected to activate Faviconize or disable it, otherwise if you have favorite urls that you want to open always faviconized you can set them in the extension’s preferences and it will be activated automatically.
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