As per the title of this question. Simply saving an interesting thread for later - how does that work on this Q&A site?
To the left of your question are two arrows to vote up or down. Beneath that is a star - click on it to bookmark the question. You can view all your bookmarks through your account page.
Technically this should be asked in the Meta site, where questions about StackExchange and the running of this site can be answered.
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