What changes in 1.19 have you found that were undocumented?
Here's what I've found so far...
Spell Immunity is now a tactical combat spell.
Kingdoms now get diplomatic capital based on the sov's charisma when researching refined diplomacy.
Lord Markinn has had his organized trait stripped from him.
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I support the spell immunity change, but that was something big enough to make it to the changelist.