In my personal survival world, I have actually found and recorded the location of 82 separate villages (only including 1.14 or newer), and have not found a single cat of the "Jellie" variant. At first I figured they were just rare or I was unlucky, but I now have every advancement except A Complete Catalogue (tame all cat variants).
I spent some time on sites such as reddit and learned that I am not the only one who is incapable of finding Jellie cats
They can be spawned using the cat spawn egg, about as frequently as other variants. However, I do not think they are spawning in villages at all.
Thank you for your report!
However, this issue is a Duplicate of MC-147591.
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