I believe the extension causing the url block is "Cloud Convert" : https://chrome.google.com/webstore/detail/cloudconvert-convert-anyt/kdmjifkppcjphfoplcicglcfcpbdoibo?utm_source=chrome-ntp-icon
Only when enabled in chrome does this "Address has been blocked" notification pop up. The website itself (https://cloudconvert.com/) doesn't cause any issues, just having the chrome extension causes issues.