Twitter knows you took a screenshot, asks you to share instead | Ars Technica – https://arstechnica.com/gadgets/2022/10/twitter-knows-you-took-a-screenshot-asks-you-to-share-instead/

I would say that, fundamentally, no website should ever be able to tell if you have taken a screenshot. Any browser that is giving them that kind of information is failing in its basic duties.