Since updating to Firefox 28, videos on Youtube will display a spinning wheel for some time, only play one or two seconds of the video, and then go to a Youtube ‘an error has occurred’ screen. At this point, Flash will crash, hanging Firefox for a minute or so. This occurs whether I am using the HTML5 player or the default player. The same videos worked fine previously in Firefox 27, and still work fine over the same wifi connection on Chrome for Android. A similar issue had occurred under Firefox 27, but only if the video was embedded in another site. Vimeo and Facebook Video still work fine: the problem seems to be specific to Youtube. Everything else on the Youtube site itself works; it's only videos that are malfunctioning. I am running the latest Firefox and Flash updates on Windows 7 64-bit, with Tree Style Tab, Download Statusbar, Adblock Plus, Foxyscrobbler, NetUsageItem, and Pocket. The issue still occurs with all add-ons disabled in safemode, and with just Adblock disabled (my first thought was that perhaps Google had changed ad delivery in a way that caused ABP to break videos, but this doesn't appear to be so). Does anyone have any ideas as to what's gone wrong? :)