I don't know if this is a bug or if this is intentional.
Place a redstone dust and switch it to "dot" mode
Place anything that can redirect redstone next to it (eg. redstone block, redstone repeater, target block, etc.)
Mine the thing that is redirecting the redstone
The redstone will be back to "cross" mode
Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-184625, which has been marked as Works as Intended - this is an intentional game feature. If you have a different opinion, please visit the Feedback website.
Please use the search function in the future to prevent duplicate reports.
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