Is this still the case? Because I downloaded the latest .deb file onto a freshly-installed Kubuntu 19.04 and I'm having the exact opposite problem: It's refusing to run the installer because of a dependency on either oracle-java8-installer or openjdk-8-jre, neither of which are available anymore because they're obsolete.
@Nate I tried that and it gave me the same error.
I'd say this is less of a bug and more of an oversight; all mobs behave this way, but villagers should be specifically blocked from dropping down onto crops. Either that, or village generation needs to be tweaked so that composters aren't directly next to farms.