What steps will reproduce the problem?

place/break (with silk) a spawner

Expected output

working normal

What do you see instead?

broken

Log file of the issue/error

https://pastebin.com/RAJyYYqk

/version output?

CraftBukkit version git-Spigot-0d820fa-5717601 (MC: 1.12.1) (Implementing API version 1.12.1-R0.1-SNAPSHOT)

SilkSpawners version

SilkSpawners v4.0.1-SNAPSHOT-b425

Please provide any additional information below.

Checklist

• I am aware that issues caused by /reload are ignored
• If there is a (potential) plugin conflict, I've identified the conflicting plugin
• I have added a valid /version output
• I have added a valid SilkSpawners version
• I have attached necessary information like a screenshot, my list of plugins, config or permissions file(s)

There are no errors in console anymore, but when i place e.g. an Skeleton spawner, it immediately changes to a pig spawner when the first entity is spawned out of the spawner. After that, there will only spawn pigs.

Tested on: CraftBukkit version git-Spigot-0d820fa-5717601 (MC: 1.12.1) (Implementing API version 1.12.1-R0.1-SNAPSHOT)

This bug will not occur on 1.12 servers, i have tested it. I havent checked other versions

As a temporary workaround for 1.12.1 builds, please use an older version of Spigot/CraftBukkit by building it with BuildTools:
java -jar BuildTools.jar --rev 1374

Thanks for the report and filling in the form!
I’ll look into what’s wrong.

Also having problem, here's a startup error: https://www.hastebin.com/kigapesime.css
Version 1.12.1 newest PaperSpigot build

@baticag please add a valid /version output. Latest is outdated pretty soon and makes things more complicated to debug.

Crossreference for myself: https://hub.spigotmc.org/stash/projects/SPIGOT/repos/craftbukkit/commits/19507baf8b7903427bc3efab7118de6e7c1c931e#src/main/java/org/bukkit/craftbukkit/block/CraftCreatureSpawner.java

Sorry, my mistake...
Paper version git-Paper-1173 (MC: 1.12.1) (Implementing API version 1.12.1-R0.1-SNAPSHOT)

@baticag and @FrankHeijden please give https://ci.dustplanet.de/job/SilkSpawners/441/ a try and tell me if everything is back to normal!

Same issue, once a spawner is placed and one mob spawns it will change to a pig spawner.

Also the problem with changing to pig, very urgent

This is a vanilla bug, and recently fixed by the Spigot team. Latest dev build will be promoted soon! Please run BuildTools again to have a fixed CraftBukkit/Spigot version.
More information: https://bugs.mojang.com/browse/MC-92282 and https://hub.spigotmc.org/jira/browse/SPIGOT-3496