Some large, image-heavy documents take a while to sync. Rather than having to repeatedly switch to a tab to check if an update has completed, it would be nice to see a badge (perhaps with a number if multiple documents have synced) on the favicon to indicate that the new version is available.
Vivaldi takes on a red color when a Gmail tab is active, making for a contrast challenge, but the important thing is to see the badge on the Sketch tab favicon.
