Firefox’s AI assistant will run on European models. Mozilla and Mistral announced on 16 September that Mistral Small 4 is coming to Smart Window, the browser’s AI feature, which remains in beta.
The two accounts differ slightly on where. Mozilla describes the rollout reaching Smart Window beta users in the US and Canada, with France the first new market to get official French-language support and more of Europe later in 2026. Mistral’s own post says the feature is live in France and North America, with the UK and Germany expected later in the year. Both stress that users can still choose from other models.
They also differ on data. Mistral’s post states that conversations are not saved on Mozilla’s servers by default and that partners including Mistral agree to zero data retention. Mozilla’s post makes the general case for privacy, control and choice but does not set out that commitment in those terms. If zero retention matters to you, the version that binds is whatever appears in Mozilla’s own documentation, not either blog post.
Why it matters: Mozilla frames the deal as resisting a world where a few closed-model companies own the browser, the search engine and the model at once. Whether model choice in a browser becomes real, rather than a settings menu nobody opens, is the open question.