We need more control over the feature. Even just the ability to select text, right click, and have a "Translation" menu would be huge. Looks like there is such a feature, but it doesn't let you pick the language pairs, which is the most basic requirement of translation.
https://support.mozilla.org/en-US/kb/website-translation has the text: "A new Translate selection feature has been added starting in Firefox version 128, that enables you to highlight and translate selected text."
Edit: Sorry, I misread the comment to say that there was no such menu item. Edited to reflect this.
The UX is not polished, and not responsive. No indicator that translation is happening, then the interface disappears for the translation to materialize, with multisecond delays. All understandable if the model is churning my mobile CPU, but it needs a clear visual insicator that something happening
Those are all features using AI and features I consider to be useful
EDIT: Oh, I've found a context menu item-list.