I have a server on 1.18.2 with the same problem, it happens in single player too. When I use the profiler, light_updates is taking 80.01% of the tick time
I have this problem, and I optimized my world, in that moment it solves, but, if I enter a nether portal and go back, the problem appears again, and the sky light is 15 again under blocks
I have a server on 1.18.2 with the same problem, it happens in single player too. When I use the profiler, light_updates is taking 80.01% of the tick time