What i expected to happen:
Commandblock: /testforblock ~ ~1 ~ wall_sign 3

will activate a comparator coming out of it.
What happened:
Command that previously worked absolutely fine now only displays an error message in the command block saying that the block did not have required NBT keys
Steps to reproduce:
-Put down a Comm. Block with a comperator facing out of it.
-Place a Wall Sign over the command block facing south with text on its first line saying "test"
-Put this command in the command block:
"/testforblock ~ ~1 ~ wall_sign 3

"
-Activate command block