When attempting to select multiple actors in the level that contain Child Actor Components, if you right-click to edit the properties of the selected actors, it will deselect any others that you have selected other than the actor that you have right-clicked on. This only occurs with actors that contain Child Actor Components.
Found in 4.10 binary. Reproduced in 4.9.2 binary and Main CL 2777621.
1. Open the attached project
2. CTRL + Left Click to select the two Stack actors
3. Right click on one of the Stack actors
Result: Any selected actors other than the one you right-clicked on are unselected, preventing you from editing the properties of multiple actors at once.
Expected: The other actors would not have been deselected upon right-clicking.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-24025 in the post.