Since Minecraft 1.14 officially blocks like stairs can block light in one direction while letting it through from others. Light cleaner now also supports the base functionality of this.

Other changes:

• Fixes some 1.16 issues with incorrect light heightmap calculations
• Shows in status message when paused due to being low on available memory
• Performance improvements for (async) chunk loading
• Shows what stage of cleaning it is (loading chunks, cleaning, applying data)
• Improve exception handling (failed to load chunks, deadlocks, hangs)