Kerbal Space Program

Moused over a part in the VAB menu. It proceeded to grow in size until it was larger that the scene. It spammed this error:

ArgumentOutOfRangeException: Argument is out of range.
Parameter name: index
at System.Collections.Generic.List`1[AvailablePart+ResourceInfo].get_Item (Int32 index) [0x00000] in <filename unknown>:0
at PartListTooltips.GetPrimaryInfo (.AvailablePart aP, Int32 maxLines) [0x00000] in <filename unknown>:0
at PartListTooltips.ShowTooltip (.EditorPartIcon part, .AvailablePart aPart) [0x00000] in <filename unknown>:0
at EditorPartIcon.MouseEnter () [0x00000] in <filename unknown>:0
at EditorPartIcon.MouseInput (.POINTER_INFO& ptr) [0x00000] in <filename unknown>:0
at UIButton.OnInput (.POINTER_INFO& ptr) [0x00000] in <filename unknown>:0
at AutoSpriteControlBase.OnInput (POINTER_INFO ptr) [0x00000] in <filename unknown>:0
at UIManager.DispatchHelper (.POINTER_INFO& curPtr, Int32 camIndex) [0x00000] in <filename unknown>:0
at UIManager.DispatchInput () [0x00000] in <filename unknown>:0
at UIManager.Update () [0x00000] in <filename unknown>:0

(Filename: Line: -1)

It happened with two different parts. Both were tanks from the LazTek SpaceX pack. No plugins installed. No visible errors with the CFG file.