Transform variable values in a Control Rig cannot be copied or pasted onto

When trying to copy/paste values from anything to a Transform variable's values, it will not happen. Additionally, you cannot copy/paste anything from a Transform variable. I repro'd this 3/3 times.

I tested this on Binary using 5.0.3 at CL20979098 and this does not occur.

Easy work-around is to simply copy/paste each value manually.

1. Create or open a project with the Third Person template assets
2. In the Content Browser, search for and open CR_Mannequin_Body
3. In the Rig Hierarchy, select the head_ctrl and set the X Translate to 10
4. Hover over the Location row and hit Shift + RMB, or Right Click > Copy
5. Go to My Blueprint 
6. Create a new variable and change it to Transform then compile
7. In the new Transform variable in the Details panel, under Default Value, expand the options to see the Transform values
8. Hover over the Location and Shift + LMB, or Right Click > Paste

Expected Result: The Location value pastes to the Transform variable

Actual Result: The Location value doesn't paste to the Transform variable and the option to copy or paste from the value is grayed out