[Feature Request] Bookmark or read later option for files

Can you please add an option in GitHub which will allow users to bookmark a file to go through later. I know similar option can be found in `Pocket` etc but something `in-house` will be great :-)

No file, test, or entry point is named. Start by examining the browser-oriented JavaScript wrapper and determining how a file could be identified, saved, and retrieved for later reading. Done criteria still need to define the bookmark flow and persistence behavior.

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