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We're running the same Unity version and OS then. Odd.

Which platform is Unity set to?

Does the error actually break anything, or does it appear to be working fine otherwise?

Vector 3 will have a color picker later, but it will not be "replaced" by a picker. Technically, a color is limited in the 0-1 range, whereas Vector 3 can have negative values and values beyond 1 :)

I'm unable to reproduce this it seems! Which Unity version are you running? How does the call stack say in the error message?

Hey there! I'm on 4.2, so I'm not able to test it. Would love to see a screenshot of it though

I can't seem to be able to reproduce this bug, the lines disappear as they should. How do you trigger it?

Per-vertex lighting is currently not really supported, so it's expected :) It's of course a planned feature, just not a very high-priority one at the moment!