There is none, this is all AI=bad knee-jerk reaction. From what I can tell, so far Firefox has 3 ML-based systems implemented:

• Site / text translation - fully local, small model, requires manual action from user
• Tab grouping suggestions - fully local, small model, requires manual action from user
• Image alt text generation (when adding images to a PDF) - fully local, small model, looks like it's enabled by default but can be turned off directly in the modal that appears when adding alt text

All of these models are small enough to be quickly run locally on mobile devices with minimal wait time. The CPU spikes appear to be a bug in the inference module implementation - not an intended behavior.

Firefox also provides UI for connecting to cloud-based chatbots on a sidebar, but they need to be manually enabled to be used. The sidebar is also customizable so anyone who doesn't want this button there can just remove it. There's also a setting in about:config that removes it harder.

I actually really like the way Mozilla is introducing these features. I recently had to visit another country's post office site and having the ability to just instantly translate it directly on my device is great.

Same here, I'm on 141.0 Linux. No tab grouping unless I group them. I do see the ai button but have not bothered with it.

I remember tab groups showing up one day by themselves maybe a week ago, and then I quickly clicked about two buttons and now they're totally gone and I almost forgot they were a thing. But likely if I had summarily clicked 2 different buttons it might have been turned on without me realizing it, and that would cause the model to be downloaded and the CPU cycles to be spent (at least if I kept the tab groups on)

Still waiting for this bloat to show up, and I'm on the latest update.