У вашего броузера проблема в совместимости с HTML5
McAfee is't a bad anti virus. But it sure is annoying. The exclusion system also does't work too well for example we can't exclude a folder so we have to exclude files one by one. For some, it could be better to just turn it off when it keeps deleting stuff but do make sure that the program you're using is safe and not malware. The reason McAfee and other anti viruses detect files which you know are safe is because of false positives or because the program is not signed and it's obfuscated/Encrypted whatever..