I am playing on a realm
Writing on signs will seem to work as normal at first. However, once you dye the sign, apply glowing effect, or logout. The sign data will be gone and the sign will appear blank. Using ctrl+pick block and then placing the sign with the copied NBT data will also result in placing a blank sign. I have tried this in different chunks. No matter what, the end result is the same.
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Thank you for your report!
We're tracking this issue in REALMS-9231, so this ticket is being resolved and linked as a duplicate.
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