There's a related issue on GitLab:
And a sort of related discussion from back in March:
However, no one has yet, to my knowledge, actually suggested a drafts feature for comments and topics, so I thought I'd take advantage of some free time to write something up.
Basically, I think it would be nice if, when writing a comment or posting a topic, we could save a draft of that topic or comment to Tildes to be picked back up later on.
So, something like a "Save draft" button next to the "Post topic" button on the "new topic" page and a "Save draft" button next to the "Cancel" and "Post comment" buttons when writing comments is how I imagine this working. It could very easily work in other ways though. Also, if this were to get implemented, I think it'd be very nice if there was an opt-in option for comments or topics whose tab gets closed to be automatically saved as drafts (and maybe we should only retain drafts for thirty days, or whatever).
As for accessing drafts, I'm imagining that a user visiting their own profile page might see a "Drafts" button up near the top, next to the "All posts", "Topics", and "Comments" buttons. After clicking the "Drafts" button the user would be brought to a page listing all of their drafts. Breaking convention a little bit, they would filter between all their drafts, just their topic drafts, or just their comment drafts via a dropdown menu like how you currently sort your posts, topics, or comments on profile pages. So, filtering between the types of drafts would work like how we can sort our posts, comments, and topics on our profile pages.
I understand that differs a little from what users might expect so, if we really wanted to, we could just add "Topic drafts" and "Comment drafts" buttons at the top of profile pages instead. That would be more in line with how we currently choose to view just our comments or just our topics.
Anyways, once a user finds the draft they want to open, I imagine they ought to be able to click an "Edit", "Link", or some other button to take them back to the place in a comments page where they were originally writing that comment, or take them back to the "new topic" page with their restored draft. However, it might also be useful for users to be able to post drafted comments directly from their profile page without having to re-visit the comments page the draft was written for. Although, this would mean that users would be allowed to bypass the context of the discussion they're replying to, including any changes made since their last visit, so I'll leave that up to y'all to discuss.
And that's about it, actually. There are a ton of additional details that (I suspect) would need to be figured out to implement this, but I'm going to leave that to the folks smarter than I.