A prototype is available, though it’s Chrome-only and English-only at the moment. How this’ll work is you select some text and then click on the extension, which will try to “return the relevant quote and inference for the user, along with links to article and quality signals”.
How this works is it uses ChatGPT to generate a search query, utilizes WP’s search API to search for relevant article text, and then uses ChatGPT to extract the relevant part.
You are 100% sure that there is no mention of Wikipedia being integrated into Firefox/Chrome in any page? How thoroughly have you checked?
Due to Russell’s Teapot, I cannot be thoroughly sure of that, at least in article space. However, that does not mean your claim stands, unless you find a mention.
In principle, the media has no reason to cover this, so no mention should exist.