Whenever a map is flipped "upside down" in an item frame, it appears significantly darker than normal. See attached: https://photos.app.goo.gl/CCtUZHfgF7BFkg5E8
(note that it may take a while to show up)
Environment
I am using Java Version 8 Update 171.
Computer Specs:
Processor: Intel(R) Core(TM) i7-2600 CPU @ 3.40 GHz 3.40 GHz
Installed Ram: 16.0 GB
System: 64bit OS, x64 based processor
Duplicate of MC-130258.