Thanks for those. I apologize, I should have asked this earlier: Would you be able to visit a couple of the threads you mentioned and post some screenshots in this thread showing that you don't have the ability to post in them?
Are you using any antivirus? If so, what software and version? As you are seeing this in two different browsers, it seems I could rule out a browser extension as being the cause. An Antivirus software would affect both browsers.