Lists have two new field types. A Channel field holds one channel or several, and a File field holds files already shared in a conversation. Press a channel to open it, or a file to open it in a new tab. Everyone sees only what they may open: anything else reads “A channel you can’t open” or “A file you can’t open” and never shows its name. Saving an item keeps what you couldn’t see, a deleted channel or file drops out, and a saved view’s filter tells nobody of a channel they can’t open. Filter by a channel, sort by name, and fill these fields from a form, a spreadsheet import or a workflow, which only accepts a channel that the workflow’s publisher and the person who started it may both open.
Nobody administers a direct message, not even the workspace’s owner: the conversation’s menu offers no channel settings, the other person’s attachment cannot be given a public link or filed into folders, their canvas keeps the sharing they chose, their poll and the activity they started in a call stay theirs, and automatic AI notes are not a conversation’s setting. The Filter button counts only filters that narrow the list.