Hi, IsaaxIsNotTaken
Welcome to the Microsoft community.
This issue is likely caused by a Group Policy that enforces the installation of a malicious extension. Issues related to Group Policy are beyond the scope of support provided by us. However, we can offer some basic suggestions. If the problem persists, you can visit Microsoft Learn to seek further assistance.
Please check whether there are any Policies present under this address. If there are, click into them, check the path, and send it to us.
edge://policy/
(For example)
You can also try using the following commands to clean up the registry where Policies are stored. Please run CMD as an administrator and enter the following commands.
REG DELETE "HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Edge" /f
REG DELETE "HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\Edge" /f
Microsoft Edge - Microsoft Q&A
Best regards
Tommy Jin | Microsoft Community Support Specialist