Duplicating a group of overlapping stationary lights that produces the red 'X', and setting the copied group to 'Static' or 'Movable' will maintain the red 'X' on one of the light components.
Note I discovered this is actually just a Editor UI error. After rebuilding the scene's lighting only the original red 'X' produces the error message within the log. It almost appears as if there are two sprites overlapping one another in the duplicated group. The Static light sprite and the red 'X' stationary sprite.
Regression?
Yes, this issue does not occur in the binary release of 4.12.5 - 3039270
1. Download and Open attached project.
2. Select all the point lights in the scene.
3. Duplicate and move the duplicated group of lights so they don't overlap the original group.
4. Set their mobility to 'Static' or 'Movable'
Outcome The red 'X' persists on the duplicated point light
Expected The 'X' disappears after setting the mobility to 'Static' or 'Movable'
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