Find the list and remove any suspicious websites you don't recognize. Remove Suspicious Extensions :
Requests to download and install a specific "video player" or "codec" to view online content are almost always scams or malware delivery methods
Some popular video download players include:
If you are having genuine trouble playing a file you already own or a video from a trusted source, use these verified methods instead: How to Fix All Problems of Video Not Playing in Windows
Software that changes your homepage, default search engine, and tracks your browsing history. How to Stay Safe How to Easily Download Embedded Videos Using DevTools