Saving/bookmarking/archiving threads and views on subreddits, in anonymous mode

First, thanks for making this app, I got it off F-Droid and it's better than constantly rewriting www.reddit to old.reddit.

There's really two issues here, which can be split if necessary. I attempted to look for related issues and previous work, but didn't find much; the issues are linked at the bottom.

1.1. bookmarks in anonymous mode
I would like to be able to "bookmark" posts while in anonymous mode.
A current workaround is to share the post to say, a text editor app, but it takes me several clicks to get through that and is generally a pain and ruins the flow.

1.2. If this was implemented it would also be nice if you could select multiple bookmarks from the list to export as text, or at least export all the bookmark data in some processable format.

2.1. as a corollary: archiving and archive export:
It would be useful if snapshots could be taken of a full thread and of a current view of a subreddit.
As far as I can tell, the subreddit view archiving seems to be implemented? I don't know about exporting though.
It would be natural to be able to view archived threads in the UI just like for subreddits, though it's probably a good idea to add some indicator that we are viewing a static archive.

It would be good to provide the capability to export these snapshots to other tools as say, json or somesuch.

My underlying principle here is that if I use redreader for discovering new knowledge and reading something, I should be able to go back and do so again at a later time even if the dataon the internet is gone. I don't want the searching work and content to disappear from under me. Furthermore it would be good to be able to cross-link the found things in e.g. my personal wiki.

2.2. As a corollary to this, it would be cool if redreader could import archives in it's format.

related:
https://github.com/QuantumBadger/RedReader/issues/625 Option to save a certain thread?
https://github.com/QuantumBadger/RedReader/issues/556 See Saved Comments
https://github.com/QuantumBadger/RedReader/issues/150 [feature request] Offline Mode - cache comments
https://github.com/QuantumBadger/RedReader/issues/136 Add option to save a comment

Begin by reviewing related issues #625, #556, #150, and #136, then check the existing subreddit-view archiving behavior described here. Split bookmarking, archive viewing and export, and archive import into separately scoped requirements; the work is done only after each capability has an agreed format and UI behavior.