Daniel Stancu

​ Same here, since i installed KIS 21.1.15.500 the issue with youtube appeared. Access the YouTube page, click the SIGN IN button, and, although it looks like I am signed in when i click the account button it looks like this As described above nothing works to fix the issue, I have to exit Kaspersky internet security entirely, clear cookies/cache, restart Firefox and after that is working again. Here is how it looks when kaspersky is disabled and YouTube is working as it should ​

Same here, since i installed KIS 21.1.15.500 the issue with youtube appeared. Access the YouTube page, click the SIGN IN button, and, although it looks like I am signed in when i click the account button it looks like this As described above nothing works to fix the issue, I have to exit Kaspersky internet security entirely, clear cookies/cache, restart Firefox and after that is working again. Here is how it looks when kaspersky is disabled and YouTube is working as it should