Editing the value of an Array Variable in an Actor Component's bp Details panel will collapse the expanded array

Editing the value of an Array Variable in an Actor Component's bp Details panel will collapse the expanded array.

Found in 4.7.3 but also reproducible in Main 2491982.

Another user reporting the issue:

https://answers.unrealengine.com/questions/205562/editing-default-values-in-array-hides-the-ui.html#answer-205708

1. Open QA-Game
2. Create a new bp, "Actor Component' class > Open the bp
3. Create a new variable, (type doesn't matter) > Make it an Array
4. Compile, then add multiple Elements to the array variable
5. Click the drop-down arrow to expand the array elements
6. Change any value

Results: If any element value is changed, the Default Values will collapse

Expected: For the Default Values to stay expanded like in a standard actor bp