When I use the test for command in a command block and have a negative value it seems to corrupt it and make it all #'s
Ex:testfor @a 1 1 -1
It seems to only happen when its the Z value but I've had it happen once with an X value
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Thank you for your report!
We're actually already tracking this issue at MCPE-106296, so I will resolve and link this ticket as a duplicate.
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