Steps to Reproduce: 1.open a page with a jpeg such i gave you 2.right click 3.click set as wallpaper 4.try to set as wallpaper that's what i can't do Actual Results: nothing and its the problem Expected Results: set the jpeg as my wallpaper i use noia extreme theme
I have tested your issue on Win 8.1, WIn 10 with latest Fx release (46.0.1, Build ID:20160502172042) and latest Nightly (49.0a1, Build ID:20160508030214) and could not reproduce it. I have opened several pages with jpeg images and I could set them as a desktop wallpaper. Is this still reproducible on your end ? If yes, can you please retest this using latest FF release and latest Nightly build (https://nightly.mozilla.org/) and report back the results ? When doing this, please use a new clean Firefox profile, maybe even safe mode, to eliminate custom settings as a possible cause (https://goo.gl/PNe90E). If this is still reproducible for you, please provide more details regarding the Firefox version that you use and the link for which you encounter this issue.
Considering the fact that I cannot reproduce this and the fact that the reporter did not answered to my request until now, I will mark this as Resolved - Worksforme. If anyone can still reproduce it, feel free to reopen the issue and provide more information.