Please note that we do have a bookmark option as well. At the top of each post is a bookmark icon that you can click on to bookmark a post. You can use that in the case of threads that you want to come check up on again later. I've added a screenshot, with the bookmark button highlighted green below.
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If you want to see all the posts that you've bookmarked, you'll find a list of them in the Bookmarks tab of your account menu. I've posted a screenshot of that below, too.
View attachment 10718
Also, on the account menu, there is a link to "Your content", which will show you a list of all the posts/threads that you have posted on the site. That way if you forget which threads you've replied to recently, you can just find them all right there.