Created attachment 654142 [details] Screenshot showing how it looks From a new session: download a file, wait for it to finish. After, download a file that will be finished almost instantly, for instance a HTML page. A translucent green box appears over the arrow icon on the Download button (see screenshot)
Updated: This happens everytime a download finishes and the download window "bubble" is hidden.
Seems like a duplicate of 758515 (Note that the Status page of the feature says to look for bugs blocking 564934 and links to a 1 level deep bug tree, which doesn't list many filed bugs. Maybe this should be clarified?)