Binding a tool tip in UMG to a text variable will not work unless the tool tip already has a default value

A tool tip that has been given a binding will not show up unless the tool tip has been given a default value.

1. Open Editor
2. Create a new Widget blueprint
   Right click the content browser > User Interface > Widget Blueprint
3. Open the Widget Blueprint
4. Add an Image Widget to the Designer's tab via the Palette panel
5. Select image
6. Create a binding for the tool tip
   Details panel > Behavior section > Tool Tip Text > Bind > Create Binding
7. Create a new text variable "ToolTip"
8. Make the "ToolTip" variable public
9. Set the "ToolTip" Variable as the return value of the return node (attached image for reference "BlankToolTipIssue2")
10. In the event graph > Recreate the blueprint in the attached image "BlankToolTipIssue1"
11. Compile and save
12. Open Level Blueprint and recreate the blueprint in the attached image "BlankToolTipIssue3"
13. Play in Editor
14. Hover mouse of the image widget
15. Notice there is not tool tip
16. Stop PIE
17. Open Widget blueprint
18. Add a default value to the image's tool tip text field
19. Run PIE again
20. Hover mouse over image
21. Notice the tool tip is now working as expected