Both on the API (which I'm using for openwebui) and on grok.com.
It might just be that twitter is a disproportionate amount of their training data, leading grok to believe in a world where twitter is much more ubiquitous than in our current reality. And the grok.com version might be unintentionally biased because it has a tool to search twitter and the system prompt instructs it on how to use it, leading to a sentence about X to always be in the prompt in that version. I'm not at all claiming that it has to be an intentional plot to promote twitter, it might just be an accident. But it is a very perceivable bias
It might just be that twitter is a disproportionate amount of their training data, leading grok to believe in a world where twitter is much more ubiquitous than in our current reality. And the grok.com version might be unintentionally biased because it has a tool to search twitter and the system prompt instructs it on how to use it, leading to a sentence about X to always be in the prompt in that version. I'm not at all claiming that it has to be an intentional plot to promote twitter, it might just be an accident. But it is a very perceivable bias