At this time, System Messages from Roblox can be deleted, but regular messages from other players cannot. That said, if you would like to clear messages out to maintain a tidy inbox, we do have the Archive action. This will move the message from your inbox and into your Archive tab.
To archive a message while viewing it, simply click the Archive button located below the navigation tabs. You can move it back to your inbox later by finding the message in the Archive tab, viewing it, and clicking the Move to Inbox button.
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