how do i disable my browser to keep opening cadforum website for no apparent reason?it is affecting my productivity as it keeps opening intermittently. 

Hi, it is not a malware - it is a standard version-check mechanism, notifying you about a new version available (see the command line). Either update the LISP app or disable this automatic checks (once a week).See https://www.cadforum.cz/en/how-can-i-find-out-which-version-of-lisp-freeware-is-loaded-tip14399