I think if something can be done as an extension then there is no need to do it as a fork of the existing software.
Are there any differences b/w nanobrowser and brwoserOS? like some functionalities that only browserOS could do and not nanobrowser which are worth mentioning?
From a quick scan of the page, they seems to use some kind external LLM API keys. The appear of the poster project seems to be locally run LLM (assuming tranfomer.js ).