Sin with Fervor
This is a tiny hack to prevent the collapse of Catholicism.
Nerf the sin and virtue events. At the time of writing, to -0.1 for a sin commited by a normal priest and -2 for a sin commited by the head of religion. Virtues give +1. The general fervor gain is nerfed to +0.1 instead of +0.3 per month, so that not everyone non-Catholic sits at 100% fervor all the time.
Note that Catholicism’s fervor still tanks regularly due to its many succesful Holy Wars. This is OK from my point of view to prevent snowballing.
