Something worth exploring if possible. Mhaigh mentioned this is related somewhat to adding "search" to settings. So I thought I'd file it first. Temporary placement: overflow '3-dots' in tabs tray
Note: this functionality is accessible from the awesomebar, but it's not very discoverable.
I think our switch-to-tab UI solves this problem for us, and I'm hesitant to add another search UI in addition to the regular awesomescreen UI. If we think that users really want to look for open tabs, perhaps we should prioritize open tabs more in our frecnecy algorithm, although I would think they would be high since they should have very high recency (you just visited it!).