The fourth sim update promising ATC updates, icing options and sim improvements is here! This update brings improvement to navigation, weather and a whole lot of aircraft changes.
Do I need to do anything with add-ons in the community folder?
While you should be able to update your game just fine when leaving your add-ons in your community folder, Asobo still recommends removing them first before updating and then adding them back in after the update has finished installing. If you run into any issues, just make sure to remove them again since some add-ons might break with the update.
What is the file size of the update?
The main app update is approximately 250 MB and the downloadable content in-game is approximately 3.5 GB depending on your game version. Do note that the actual download size may vary depending on what version of the game you have purchased.
The patch notes can be found here.