For Minecraft 1.16.3 I have been trying to build a wheat or bread farm that is fully automatic, however with the newest updates to 1.16.3 villagers head straight to the compost bin to get rid of empty inventories, so I can't find a way to collect the wheat effectively and timely. Does anybody have any automatic wheat/crop farms functioning in Minecraft 1.16.3 (or 1.16.4)? If so please post some instructions.
Pretty simple solution however it requires a lot of seeds, redstone, and rails. Give the villager eight stacks of seeds and with a dispenser give the villager a full set of armor (The villager must have an empty inventory beforehand). This will fill up all 12 slots a villager has an make it impossible for it to pick up any wheat or bonemeal. After that simply stick him in a farm with a composter and have a hopper minecart collection system beneath the farm.
An upside to making a farm like this one is that a farmer takes no time find and give bread to another villager, which isn't much but if you're going to maximum efficiency this will help if only a little. I will admit though I have not tested if the villager gets more seeds than he puts into the composter so that might be an issue.
I do not have a wheat farm design I can share with you because all of my wheat farms are improvised based on what I need and what I have. But I believe making a hopper collection system and a small plot of land for a single villager to farm should be simple enough to build.
Edit: Villagers have eight slots plus four armor slots. The armor is not required.