Rapid clicks on pool selection creates multiple from pins about zui

[philrz]

I've reproduced this problem in the attached video using GA Zui v1.5.0.

I've not been able to reproduce the problem on macOS, but it does reproduce fairly reliably on Windows. It seems that a key ingredient is for the system to be underpowered or under heavy load, which I assume is essential in stacking multiple clicks before the app has a chance to react. In the repro video I'm using an AWS Windows 4-core VM, and so I have Cygwin installed and have four cat /dev/urandom > /dev/null & processes running in the background to tie up all the CPU. Now when I start a new Query Session and left-click rapidly on the pool name, I can indeed create multiple from pins.

Repro.mp4