The redstone torch turns off (does a burnout) when is used in a redstone clock. That is a bug because doens't happen on Minecraft PC and it's "against" the Minecraft redstone physics.
Comments 6

I'm rather interested to see an example of this, because I think it would be interesting to see if this relates to any bugs I have reported (a few redstone torch bugs).
Does this bug still appear in 0.13.1? If so please respond.

Does this bug still appear in 0.13.1? If so please respond.
@AMAN4700 No, this was fixed. Thanks!

@AMAN4700 No, this was fixed. Thanks!
I'm rather interested to see an example of this, because I think it would be interesting to see if this relates to any bugs I have reported (a few redstone torch bugs).