This bug is caused by the sign facing different directions, such as North/South directions making the sign text darker, and the East/West directions making the sign lighter. This can be fixed by using settings, but it takes a toll because you have to turn down quality of blocks.
Environment
I use the Java Edition of Minecraft. I do not have any viruses. I play on a typical desktop, It is not my system that is causing the bug, as many people experience this bug. I use Windows 10.
Duplicate of MC-33304, an issue marked as WAI.
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