I was toying with the idea of a browser archiving mode for Firefox that would allow something like or "save local copies of everything in my history" or "just save local copies of all my bookmarks". I sketched out a few use cases. <
https://wiki.mozilla.org/Permafrost >
Social and technological hurdles for development were big enough that I never pursued it past that. One issue is that the Firefox product inside Mozilla was starting on a trajectory towards becoming increasingly inward-focused, disfavoring ideas that didn't come from within, and following a more corporatized product development approach. So what one would need to do (and ideally everyone working on new, discrete features should be doing, anyway) is to start out by building it as an extension to work as a proving ground.
The problem there is, in order for that to work in any sort of reasonable way, changes to Firefox itself would need to be made (APIs reworked) so that the surface exposed to you there is not one that's running orthogonal to what you need. So in order to develop the thing, you'd need to get some cooperation to get these non-trivial core changes upstream. GOTO 10
AFAIK (I used to be on top of a huge part of what came out of the Mozilla firehose, but I don't do any of that anymore), the whole situation is no better today (and really, from what I understand, much worse). Chromium might be better there, but I really have no idea.