So, I am not a robot. I am trying to post external links in a topic which needs external links (It's a list of videos, therefore needs external links). Robot question stops me and I can press million times on No, I am not a robot, it will blue circle for an hour and then whole page will go to grey. (My internet is quite fast, good upload speed as well, so no issues there. This is only website I encounter problems with in last 5 or 6 years.) If I refresh it brings me on the same page. Or it kicks me out, without edit being submitted.
However, I’ll mention it here, the system you’re most likely referring to is named CAPTCHA, a system that identifies if a user is confirmed in the system, once a users confirmation is reached, the system will be removed when links are added, this typically takes a bit to be autoconfirmed. This should help you provide some insight.