#1 Original Report
Tested it out with a weapons computer. Linked the computer to itself with V and it became invisible in the weapons menu. Pressing V on it again (unlinking, you can't see it though) makes it visible/usable again. You get the error message at the top right but it doesn't seem to stop you from doing it. This is probably before 0.1595 but I just found it out

#2
the following computers will unlink themselves from the core or from any weapon if you press C and then V on themselves, it gives you an error message but still "allows" you to change it although you don't really get a visual link. The other blocks get a slightly different message and they don't unlink from their current state so they work correctly.
It's a minor issue but some people don't know about manually linking stuff with each other and could "permanently" remove that computer from the weapons tab if they did this on accident.

Cannon computer
Missile computer
Damage Beam computer
Damage Pulse computer

The error message you get from these 4

Error: Cannot connect a block to itself

The error message you get from the others that work fine with "name of block" as the computer name you are trying to link to itself.

*name of block*  cannot be connected to *name of block*. Reason: Incompatible blocks

Might as well use the same message for all computers.