2 months ago - AndrewT - Direct link
This issue perhaps?
forum.paradoxplaza.com

Known Issue With Disappearing Steam Cloud Saves When in Debug Mode

We have discovered an issue where Steam cloud saves can disappear! This is associated with using debug_mode due to the fact that using debug your save files will not be compressed and may go over Steam's 100MB limit for save files - making it... forum.paradoxplaza.com forum.paradoxplaza.com