Organize your Mods folder (but don't move mods you downloaded using the CurseForge app). Read each mod's installation instructions. Keep a back-up copy of your Saves folder. Read the FAQ about mod use in the Resources list below. In the end, YOU are responsible for your mod use. Mods are not linked here, but if it could be easy to find an outdated version of a particular mod instead of a new update in an internet search, I provide direction on what site to download from. Consider subscribing to the thread to receive notifications by email (select 'Topic Options').
If you use mods, this thread's lists and ongoing reports can help you prevent game errors and help you avoid having to do a 50-50 of all your mods. It also tracks updated game mods and non-cosmetic updates to custom content. This thread tracks Sims 4 mods and CC that have been 'broken' or made obsolete by game updates or declared unsupported by their creators. NOTE: This thread also covers the Decemgame update to 1.103.315.
