my play button is missing from youtube/all video boxes on FB won't play either
On my mac, youtube still works on Safari, but on Firefox, the boxes are missing the play/pause button. Also on Facebook the video links go black if you click on them. Why can't I play video anymore? They all used to be ok. In fact, I 'm pretty sure Jib Jab is still ok.
Wšykne wótegrona (2)
Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).
- Don't make any changes on the Safe mode start window.
- https://support.mozilla.com/kb/Safe+Mode
Oddly, Safari had this exact opposite problem for some time. For about 3-4 months, I could only watch Youtube videos on FF, unless I changed the user agent to FF from within Safari.
Although it had no effect on the problem opposite yours, my first line of attack would always be to remove and reinstall flash.
Check that scripts are enabled in Firefox/Preferences -> Content tab, and if you are using NoScript add-on, try allowing scripts if it shows any are blocked.
Also, try going to the poster's channel and see if you can watch from there. If so, then you have the same problem Safari used to have, but with FF. As far as I know, there is no solution other than to submit a bug report. As a workaround, join the HTML5 trial on Youtube. That should allow you to watch anything with FF4 as long as the video is HTML5 compatible.