Feature Request: Saving Topics and Comments

I think the option to save a topic or comment would be a good addition. For example, I have had a ~music topic about music everyone's listening to open for over a day so that I can pick a new group to listen to each time I do homework. Sure, I could write them all somewhere, but I think it's a nice QoL improvement nonetheless.

Edit: I'd like to add to this @Ganymede 's idea of following a topic to get notified of new comments inside it. Maybe this could apply to a specific comment chain, too, since a whole topic will be a lot once the site explodes. ;)