One of the new features in the 2020 edition is the atmosphere system (/atmo 1), this menu allows you to customize its variables using input fields.
How to install:
move atmoeditor.zip to your sauerbraten root folder and
add the following lines to your autoexec.cfg file:
addzip atmoeditor.zip exec atmoeditor.cfg
and then save & exec, to open the menu just type /atmoeditor
20/12/2020: added missing fields for atmosundisk and atmosundiskcorona