In a nutshell, what’s happening is web browsers and the forum software don’t always play nice together.
Although Firefox, etc., continually release updates, the forum software I’m running here hasn’t come out with a release in a while. The software company ownership changed hands over a year ago and they’ve been operating at a snail’s pace at releasing an update. However, I do know they are working on it. I believe the next release will help with issues like this. Despite the delay in a release, there are many benefits to this product over others and I have stuck with it, as opposed to switching to another option.