I'm not sure if this is related, but it seems to be the best place to mention it:
I have experienced issues with disappearing villagers in my main world (vanilla server) for years now, and the issue has never resolved itself. We have always kept the world vanilla (though we do now use a couple of datapacks).
I make periodic backups of the world, to safeguard progress and to catalog historic moments in the world. I was just going through some of my backups, when I noticed definitive proof that villagers do in fact disappear, and not just die.
The proof mentioned is in regards to a particular villager, named Nola Perrin. He was a carrot farmer in a large automated vertical farm, well lit and with 4 iron golems for protection. I found that between different backups, he was sometimes present, and sometimes not. here are some more specific details:
June 19 2019 Backup: Day 11039 - visible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was successful
July 7 2019 Backup: Day 11263 - invisible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was unsuccessful
July 18 2019 Backup: Day 11341 - visible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was successful
November 24 2019 Backup: Day 11449 - invisible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was unsuccessful
December 11 2019 Backup: Day 11631 - visible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was successful
December 26 2019 Backup: Day 11883 - invisible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was unsuccessful
The first 5 backups were all originally version 1.13.2, but when testing, I loaded them into 1.14.4. The final backup was in 1.14.4. I do still have all of the original backups, as well as more backups dating as far back as July 30 2014. If you want copies of any of these to try and determine the cause, just let me know.
Edit: Unlike with MC-65040, the villager is not in the Spawn Chunks, nor chunks that are loaded by a chunk loader. This glitch has also occurred, though with less proof, to many different villagers in the world, in many different places in the world.
Edit 2:
It appears the issue is actually of a very different nature. I recalled that some time ago, the villager, Nola Perrin, duplicated. I believe it was while the world was in 1.13.2, though I'm unsure. I then named one of the duplicates August Perrin, and transported him to another floor of the farm.
I went back through all of the backups mentioned earlier, this time using version 1.13.2, and found the same result as when using 1.14.
It appears that the game does not understand how to handle the duplicated villager, and so it alternates between the two versions. In every backup where Nola Perrin is gone, August Perrin is present, and vice versa. Time will tell if the alternation between states persists in 1.14.4 and beyond.
migrated
I'm not sure if this is related, but it seems to be the best place to mention it:
I have experienced issues with disappearing villagers in my main world (vanilla server) for years now, and the issue has never resolved itself. We have always kept the world vanilla (though we do now use a couple of datapacks).
I make periodic backups of the world, to safeguard progress and to catalog historic moments in the world. I was just going through some of my backups, when I noticed definitive proof that villagers do in fact disappear, and not just die.
The proof mentioned is in regards to a particular villager, named Nola Perrin. He was a carrot farmer in a large automated vertical farm, well lit and with 4 iron golems for protection. I found that between different backups, he was sometimes present, and sometimes not. here are some more specific details:
June 19 2019 Backup: Day 11039 - visible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was successful
July 7 2019 Backup: Day 11263 - invisible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was unsuccessful
July 18 2019 Backup: Day 11341 - visible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was successful
November 24 2019 Backup: Day 11449 - invisible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was unsuccessful
December 11 2019 Backup: Day 11631 - visible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was successful
December 26 2019 Backup: Day 11883 - invisible, command /tp @e[type=minecraft:villager,name="Nola Perrin"] @p was unsuccessful
The first 5 backups were all originally version 1.13.2, but when testing, I loaded them into 1.14.4. The final backup was in 1.14.4. I do still have all of the original backups, as well as more backups dating as far back as July 30 2014. If you want copies of any of these to try and determine the cause, just let me know.
Edit: Unlike with MC-65040, the villager is not in the Spawn Chunks, nor chunks that are loaded by a chunk loader. This glitch has also occurred, though with less proof, to many different villagers in the world, in many different places in the world.
Edit 2:
It appears the issue is actually of a very different nature. I recalled that some time ago, the villager, Nola Perrin, duplicated. I believe it was while the world was in 1.13.2, though I'm unsure. I then named one of the duplicates August Perrin, and transported him to another floor of the farm.
I went back through all of the backups mentioned earlier, this time using version 1.13.2, and found the same result as when using 1.14.
It appears that the game does not understand how to handle the duplicated villager, and so it alternates between the two versions. In every backup where Nola Perrin is gone, August Perrin is present, and vice versa. Time will tell if the alternation between states persists in 1.14.4 and beyond.