184.108.40.206 Beta, 220.127.116.11 Beta, 1.16.220, 18.104.22.168 Beta, 22.214.171.124 Beta, 126.96.36.199 Beta, 188.8.131.52 Beta, 184.108.40.206 Beta, 220.127.116.11 Beta, 18.104.22.168 Beta, 22.214.171.124 Beta, 126.96.36.199 Beta, 188.8.131.52 Beta, 184.108.40.206 Beta, 220.127.116.11 Beta, 18.104.22.168 Beta, 22.214.171.124 Beta, 126.96.36.199 Beta, 188.8.131.52 Beta, 184.108.40.206 Beta, 220.127.116.11 Beta, 18.104.22.168 Beta, 1.13.3, 1.13.1, 1.14.1 Hotfix, 22.214.171.124 Beta, 126.96.36.199, 188.8.131.52, 184.108.40.206 Beta, 220.127.116.11 Beta, 1.7.0, 18.104.22.168 Beta, 1.9.0, 22.214.171.124 Beta, 1.12.1, 1.13.0, 126.96.36.199 Beta, 1.14.0, 1.14.30 Hotfix, 1.14.60 Hotfix, 1.16.40 Hotfix, 1.16.201 Hotfix, 1.17.41 Hotfix, 1.18.2 Hotfix, 1.18.10, 1.18.30, 1.19.0, 1.19.2 Hotfix
94243 / 95333
Edit by depressed-pho, updated by GoldenHelmet:
Original test world was unreliable because it had the observer looking at lit redstone dust across a chunk border. Test world and description updated to include other blocks on Novermber 2, 2021.
Observers looking at several kinds of blocks emit a pulse on world reloading. The attached test world demonstrates the bug. The following blocks were tested in 1.17.41 Hotfix:
|Block||Triggers observer pulse on relog|
|Lit redstone dust|
|unlit redstone dust|
|Redstone torch (lit or unlit)|
|Repeater (powered or unpowered)|
|Comparator (powered or unpowered)|
|Empty single chest|
|Empty double chest|
|Chest with item in it|
|Dropper (empty or with item)|
|Glow item frame|
|Tripwire with mob on it|
|Pressure plate with mob on it||inconsistent|
Steps to reproduce:
- Open the attached world.
- Close and open it again.
- See what the dispenser does.
Strangely, the pulse is too short (0 ticks maybe?) for dispensers to trigger so you need a repeater to make the pulse a bit longer.
I have created a contraption that, when not in use, constantly powers a series of dispensors. However, relogging with this contraption nearby unpowers and repowers the redstone, causing the dispensors to dispense their items without player interaction.
Video shows the bug, and also the Minecraft version being run