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If the user switches from one workspace to another, the contents of the clipboard are flushed, although the rest of the state of the workspace is preserved. This avoids the confusion caused when copying items in one space, then hitting paste in another and getting different content possibly copied hours ago. Flushing a clipboard when switching workspaces also enforces our view of the clipboard as a local tool with temporary character.
Restrictions to pasting items
A paste operation must not be allowed, if the currently shown item subset does not support pasting an item type of at least one of the items in the clipboard. While the subset is only a filtered view and the paste might actually work, it is totally unclear what would happen and which item it would target.
Preview of paste operation
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