bug#32932: 27.0.50; render bugs on macOS Mojave

[Aaron Jensen]

> Is it possible that ‘one line’ is the same as the height of the title
> bar?

That’s possible, yes.

> Sorry, I was unclear. I meant the compiler warnings etc. But since
> Charles sees this on 10.6 it’s unlikely it’s something new in the
> compilation.
>
> All I can think of to do is enable NSTRACE and see if you can spot
> some commonality when the problem happens.

Any particular groups you want me to include in the trace?

Aaron