Bob, I had a very unusual couple of interactions with the forum just now. The question is whether this problem was on my end or yours.
I was replying to a forum post when all of a sudden the entire web browser interface, top to bottom, got greyed out and frozen. This happened as I was trying to insert and image - just the same gray covering of the web browser window but the Insert Image window did not appear. I couldn't do anything except "x" out of the browser, which I did. I reopened the browser and was typing the reply over, when the same thing happened again, only this time after a few seconds a window popped up saying something like "we've noticed a lot of unusual activity...," and specifically citing my IP address, along with opening a Captcha 'I am not a robot" button. I should have taken a screen picture of that window, but I pushed the not-a-robot button first, and the window disappeared.
I typed a second reply to another post without a problem. Now I'm typing this message without a problem.
I've never had this occur on any website where I didn't expect it, and certainly not on yours. I'm not using VPN or TOR.
If you've implemented a Captcha, do you know what I might have done to have gotten caught by it? If you haven't, I guess I'll chalk it up to another one of those mysterious cosmic ray events.