There is a bug with the redstone texture. The texture bug happens when you place a redstone dust on a block then place a redstone dust 1 block lower to connect it. The result is a redstone dust connected to a redstone dust that doesn't display the connection texture. It is a minor bug but still disorienting.
MC-133244
Redstone texture
Resolved
Duplicate
1
Garrett Melvin
(Unassigned)
Unconfirmed
Minecraft 1.13-pre7
Retrieved
Can confirm.