I was thinking about something similar a couple of weeks ago: Wouldn't it be useful to be able to serialise browser state? I.e. saving a full package of html+css+javascript state to a compressed file on a hard disk.

Having that ability would solve a host of problems - e.g. having too many tabs. Older tabs could simply be serialised down to disk to free up ram/processing power, and read back in to exactly the same state when the user wants to interact with them again.

They would also aid in debugging, as users could send a serialised snapshot of a page as part of a bug report to help devs diagnose problems with websites.

Unfortunately however, I know far little about hwo browsers are constructed (and I have far too little time) to implement such a thing, but it's something that I've been wishing for for a while now!