private static Transferable getSystemClipboardTransferable() {
		try {
			return GClipboard.getSystemClipboard().getContents(
				DataTreeClipboardUtils.class /* not used */);
		}
		catch (Exception ise) {
			// This can happen when the system clipboard is 'busy'.
			// Ignore, as this is just to fixup action enablement
		}
		return null;
	}
Fetches any GTreeNodes from the system clipboard.

@return List of {@link GTreeNode}s that were in the system clipboard, or empty list if
no nodes or some other access error.
Ghidra/Framework/Project/src/main/java/ghidra/framework/main/datatree/DataTreeClipboardUtils.java