Some video sites won't play for me

The problem I’ve been having recently is that when I visit video sites like
and many others the video players just don’t load anymore and video doesn’t play. I noticed this started happening within the past couple months after a new update. The strange thing is that if I choose to restart the browser in safe mode with add-ons disabled the issue is fixed, but if I disable or even remove all the add-ons manually one by one to narrow down whats causing it, the issue still remains. I tried with other browsers like FF IE Edge and the sites work fine. I also tried reinstalling Adobe flash player. Thanks for any help with this.

I just updated FF to 43 and the same problem is now happening with it also. Would really appreciate some help with this.

Solved: I figured out what’s causing it. In the Privacy settings I had it set to Never Remember History which also puts it in Private Browsing Mode. If its selected the browser prompts a restart to enable and it apparently prevents videos from playing after that. Also if I select to open a new private window the videos won’t play. This is also the same with FF. I’m glad that I know whats causing it and can use IceDragon for video sites again. But there was no help from this message board at all. Over a hundred views and no response? Comodo forums are a ghost town.