Problem assigning developer to a task

[stepin]

Env: iPad Pro 10.5, the game is from App Store

Steps to reproduce:

1. open new task or bug dialog
2. scroll to the right to select a developer
3. select developer (fast)

Current result: dialog is closed without developer selected
Expected result: the developer is selected

It's easy to reproduce in my env. Very annoying when I'm tried to play.