The bug
When upgrading an old (1.7.10) world to the latest version, the color of wolves collars changes from red to orange (and possibly other colors as well).
This might not be fixable due to changes to the CollarColor
when the version information was not stored in the save file, see MC-54109.
Comments 4
Confirmed for 1.16.5. It can currently not be reproduced in the 1.17 snapshots, because loading of old worlds is temporarily disabled.
Confirmed in the current version. Other colors are also affected, they switch places:
Black - White;
Red - Orange;
Green - Magenta;
Blue - Yellow;
Brown - Light blue;
Purple - Lime;
Cyan - Pink;
Light gray - Gray.