Piston duplication bug

[Florentin-EdenSchool]

I am currently running

• SpongeForge version: spongeforge-1.12.2-2838-7.2.1
• Forge version: forge-1.12. 2-14.23.5.2838-universal
• Java version: openjdk version "1.8.0_252" OpenJDK Runtime Environment (build 1.8.0_252-8u252-b09-1~deb9u1-b09) OpenJDK 64-Bit Server VM (build 25.252-b09, mixed mode)
• Operating System: Debian 9

• Plugins/Mods:

Image link : https://imgur.com/ekqYV9H or attaching file

Issue Description

I can duplicate shulker with piston, if you make clock who active redstone who break shulker, if personn break shulker when the piston is break and the server have micro-lag, the shulker can sometimes duplicate. I think it's the same if two personns break at the same times shulker but it's not sur for this.

[Florentin-EdenSchool]

My player who find this bug say me he do just when mini-lag clock piston and break shuleker with clock and piston very fast and two shulkers can drop instead of one

[dualspiral]

I need you to do a few things and report back your findings:

• You're not on the latest recommended build. It may have been fixed since then. Try again on 7.2.3.
• Can you reproduce this with Sponge only, no mods, no plugins?
• If you can't, add -Dsponge.shouldFireAll=true before -jar in the command you use to start the server (which may be in a .bat or .sh file)
• If not, then try to figure out what minimal set of mods and/or plugins you need to reproduce this

This will help us narrow down where the issue might be.

[Florentin-EdenSchool]

I have test all and yes i can all the time make this duplication bug

[dualspiral]

That doesn't answer my questions above. Under what minimal situation does this happen? Any plugins, mods? Version of SpongeForge?

[Florentin-EdenSchool]

I have install the latest recommand version of sponge forge (7.2.3), put the -Dsponge.shouldFireAll=true and test with and without mods/plugins

[dualspiral]

What about without the -Dsponge.shouldFireAll flag (as I also asked for)?

[Florentin-EdenSchool]

Work without