Stopping worked since macOS Catalina
Hi,

I can't say it's definitely related, but since upgrading to macOS Catalina, Find and Replace has stopped working. When I hit the shortcut keys, it launches the window but it remains blank. 

![image](https://user-images.githubusercontent.com/978182/66738416-629c5c00-ee66-11e9-9298-c0ebdd604f77.png)

In fact, on subsequent attempts, it doesn't even launch the window, Sketch just crashes. Maybe it's a Sketch/Catalina problem? Anyhow, I thought I'd mention it. :)

Thanks,
Tim