Can confirm, they do disappear for a split second, and it would be awesome for Mojang to fix this annoying bug.
Still happening in 16w03a
https://youtu.be/thRs0e4u4cw?t=3m8s
You may check it out.
it still reproduces in 15w46a.
Confirmed for 15w44a, they still visually glitch.
I was editing the server.properties file, so I really do not know. I just tried it in the local environment, it worked. I will try to report it to the Panel guys.
I was using PufferPanel which might be the reason, sorry for you inconvenience...
Patrick, no thank you, it is extremely annoying when you are building something
No it doesn't duplicate... the desciptions are different and MC-59509 only applies to detector rails.
Umm Should I make this private?
And this cause item storage system to leave items in all vertical chests too causing very inconsistent timing problems.
Also this breaks hopper timers.
Kevin, if you open F3 debug screen and look on for the block type, you can see that the piston actually disappears and it shows the block behind it for a moment.