I think that (optional) AI features are fine, but the model selection only shows the big providers by default. You can enable local LLM support under about:config -> browser.ml.chat.hideLocalhost (set to false). It will check localhost:8080, which is not a great choice for a fixed port. I'd prefer if I could just point it at any OpenAI-compatible endpoint. Either way, seems to work well when serving a local model with llama.cpp.