I also noticed that if the page is refreshed during registration the image captcha doesn't change
Is this a security problem or it is normal on this forum,?
I believe it's because you're able to deal with the captcha challenge that's why you are able to come onboard to make this post, now the solution is to permanently avoid the unnecessary demands from solving the captcha by clicking on the button always stayed logged in right after your passwo colum, the page will always stayed logged in and also refreshed anytime you're logging in through your browser, welcome onboard to the forum, read the rules and don't plagiarize.