Ability to customize the favicon in a design file, prototype, or FigJam file. It could be changed to a logo, color, or first initial to identify which tab is for which workstream more easily. It would also greatly help with the scanability of any pinned tabs, which today the user is only able to see which file it is on hover preview, or knowing the sequential order of your pinned tabs.
Please Figma I beg you 
Not quite what you’re asking, but perhaps something that might work for your use case: If you have an emoji at the beginning the file name, Figma will replace the standard favicon for the file type with the emoji.
Yeah as the previous comment is showing you, you can already do it with icons. If they add this feature it will be used for sure by less than 0.01% of the users (and i’m kind).
At a moment you juste have to considere what is important or not. In this case it’s not important at all and you will just make even more complex Figma for a such feature, + the stockage of those images will make the file size bigger for nothing. Today we need to think before developping features and understand their impact on the tool and the environnement.
Would be really nice if the emojis were ignored when sorting files alphabetically
My files start with a number, especially libraries/DS files, to understand which file is first in the hierarchy.
Eg. styles are used in components.
01 - Styles
02 - Components
…
Just a quick thought I wanted to share—as the favicons for Figma and FigJam tabs are identical. It’s a small thing, but it often leads to me clicking the wrong tab by mistake.
Maybe tweaking them a bit or giving them slightly different designs could help users like me easily distinguish between the two.
Just a friendly suggestion to make our Figma experience even smoother! 
