As Mozilla envisions Firefox’s future, we are focused on building a browser that empowers you to choose your own path and gives you the freedom to explor
They're not just giving these AI companies your data...
It's an optional feature, and you would choose which model you use. If you choose not to use it, or disable the feature, nobody will recieve your data. If you want a browser without these features, Librewolf will likely be a safe choice, as I don't seem them adding this.
The only active AI feature is the automatic alt text one, and that's entirely local. The second one is a sidebar that will just open AI chat websites, which you could already do by just, ya know, looking up the webpages the regular way. No data is getting sent anywhere so far.