PRDs, specs, research and decisions — written in Markdown, versioned on every save, and attached to the posts that prompted them. Internal, always: your customers never see them.
A feature request is one sentence from a customer. The work behind it is a spec, a rejected approach, a decision someone will ask about in six months. Put all of that on the board and the board becomes unreadable.
So it lives in a document instead — attached to the post, readable by your team, invisible to everyone else. The post keeps its votes and gets one answer at the end. No sub-items, no threads of half-decisions.
A type is the question the document answers. Every workspace starts with these eight; rename them, recolour them, reorder them, or add the ones your team actually uses.
Six months later, the useful question isn't what the spec says. It's what it used to say, and who changed it. Open any version and the answer is highlighted in place.

Not a delta. Version 1 is written the moment the document is created, so the history is complete from birth.
Paragraphs, list items and code blocks are compared whole, then word by word inside any block that was rewritten.
Restoring an old version re-applies its content as a new version on top. Nothing in the chain is destroyed or rewound.
Versions accumulate — there's no retention window. Save a document you didn't actually change and nothing is written at all.
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