I've noted that under certain circumstances, it's undesirable to have the pulsing blue highlight on an object during a mouseover event. Specific instances that have come up for myself have been:
- Press-to-test warning lamps. The blue highlight makes it difficult to see the tested light.
- Translucent objects (window shades, gear handles). The blue highlight seems to make the object disappear.
- Panels / objects with a $texture assigned. The blue highlight seems to interrupt the gauge drawing process.
In the above cases, all of these have been the result of the mouse interaction occurring on a parent object; When an object is highlighted, the children of that object are also highlighted. I've always been able to be creative and find a workaround, but there are occasions when, in the case of complex animated items, the workaround is fairly difficult to implement and far from desirable.
In the same way that a flag was recently implemented to disable motion blur on a material, it would be extremely useful if we could set a flag in the material editor to disable a certain material from being highlighted with the mouse / tooltip system.