mart added a comment.
in general, it's OK.
But as this is a bit delicate part, can you do one more test?
have only the external screen enabled and primary, then detaching and
reattaching the cable from the connector.
this is a similar but not completely code path to swapping the primary screen.
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To: davidedmundson, #plasma
Cc: mart, plasma-devel, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas