Opening hint box and then multiline popup, the hint box is above the multiline popup.

Steps to reproduce:
1) Open preprocessing test dialog;
2) Do test to make error occur;
3) Click on icon in results block to see error. Hintbox appears;
4) Without closing hintbox, open multiline input field "value" or "previous value".

Result:
Hintbox is on the top of later opened overlay dialog.