Started getting this error as soon as Masque updated on 9/13/23:

1x OPieMasque/Addon.lua:260: API level 1 is not supported (current is 3)
[string "=[C]"]: in function error' [string "@OPie/OPieUI.lua"]:22: in function <OPie/OPieUI.lua:21> [string "@OPie/OPieUI.lua"]:648: in function RegisterIndicatorConstructor'
[string "@OPieMasque/Addon.lua"]:260: in main chunk

Locals:
(*temporary) = "API level 1 is not supported (current is 3)"

This was a required API change in the OPie update. It's fixed in version 10.1.7.1.