QtWebKit take eight seconds to render the page if custom fonts are used

Question

I'm trying to render an Angular.js page with custom typefaces loaded with @font-face. \

If I disable font–face rules, the page start–up time is half a second. When font-faces are enabled, it takes 12 seconds in total.

It happens both over HTTP server and file:///. I'm attaching the Webkit Inspector output to show what's happening here.

Is there a workaround for this? I'm using PyQt and latest version of Qt4. I'm launching the app from command–line with a Python script.

Answer 1

Turns out it's a legitimate old Webkit issue. I compiled PyQt5 development snapshot targeting Qt5 with newest version of QtWebKit, and the issue vanished.