Odd, I can't reproduce it now either. If it happens again I'll try to get a recording of it.
I can confirm the same behavior on 1.8.7 on 64-bit Linux, Java 8.
Floating tripwire with a frame occupying one of the string blocks does not deactivate when it should.
Tripwire on a surface with a frame occupying one of the string blocks does deactivate.
I can confirm this behavior.
my system:
os:windows xp
Ram: 4gb
Graphics: 512mb crap i know. its inbuilt.
java: 32 bit offline or jdk 7 i think.
TezzaMcJ this is not fixed for 1.4 because that's happening to me on 1.4 aswell. Sir Cloudy/Aaron the link you sent me is close but not exactly what I saw. Because when I look at the earth then it will let me see through the blocks and works like a cave finder.
Still happens in 1.9