Bloquear extension de google chrome

Hello sstabasco,

As per your query, to block extensions on chrome you can use the application control profile and block the specific application listed on the categories and apply the application control profile on the policy passing this traffic. Also please make sure if this does not work, try to enable the deep certification inspection profile.
You can use the link mention mentioned below as a reference and let us know if this helps.

https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-to-block-Hoxx-proxy-VPN-with-Chrome-extension/ta-p/195706?externalID=FD48477