I'm using:
Windows 8.1 64-bit
Firefox 26.0
AMD Radeon HD 6310
Adobe Flash Player 11.7.700.257
My flash player keeps crashing. For example, on Youtube, if I try to watch a video the flash player box will flash black, then white, then back to black and then eventually give me the Firefox plug-in crash error box.
I have tried uninstalling (by both downloading the uninstaller and using add/remove programs) and reinstalling but the problem persist. I have tried reseting Firefox through their Troubleshoot Information page. I have also tried turning off protection mode, to no avail. (To note: it once asked me to stop the plug-in because it was being unresponsive and so I did, which made the video start working again. I restarted the browser to check it if would still work and it went back to crashing. While it was working, I took the chance to disable hardware acceleration in both Firefox options and Flash Player settings.)
I have a feeling what started the problem. I had my desktop and the Window 8's Netflix app splitscreened. While I had it splitscreened, I paused my Netflix to watch a video on Facebook. This caused the flash player plug-in to crash and it has been crashing since.
EDIT: I uninstalled and reinstalled Firefox and that seemed to fix the problem. I guess when the plug-in crashed, it messed up the browser and not the plug-in.