Rumor is circulating that Firefox now has an AI chatbot feature integrated as a Firefox Labs experimental feature. Even if this is untrue, Mozilla has been following the enshittification bandwagon for so long now (more than a decade) that it's perfectly believable they will do it.
This is why I haven't called Firefox the best Web browser since 2012. It's merely the least bad major browser, and like every other major browser maker, Mozilla is hell-bent on making Firefox worse for users.
As an experimental feature, the AI chatbot sidebar is disabled by default, but it's still there, integrated in every edition of Firefox that has Firefox Labs.
Fortunately, they include an obvious clickable "Share feedback" link right next to the checkbox in the "about:preferences#experimental" page.