Bug 66384 – [Qt] QtWebKit 2.2 renders very bad-looking fonts when font-family is not specified or specified only to a generic font family like sans-serif (regression from QtWebKit 2.0)

• Component: Layout and Rendering
• Status: RESOLVED INVALID

[Bartosz Brachaczek]

Created attachment 104178 [details]
testcase

I'm using Gentoo Linux x86_64, X11. After upgrading from Qt 4.7 to 4.8-beta1 I noticed that some apps using QtWebKit started rendering very bad looking fonts. Those apps are for example Qt Assistant and Kadu IM when using its default settings. After some research I found that QWebSettings c-tor in QtWebKit 2.0 was hardcoding font families defaults that were working just fine on my system. Though in QtWebKit 2.2 the QWebSettings c-tor relies on QFont::defaultFamily() regarding default font families and that QFont method, at least on X11, hardcodes fonts that just look very bad, like bitmap fonts or something. Precisely, it is "Times" for default and serif, and "Helvetica" for sans-serif. I don't have such fonts installed on my system at all but I suppose they are somehow built into Qt as qtconfig is able to find and render them (in the same ugly way that QtWebKit does).

Attaching a simple testcase.

On a side, I also was able to confirm this issue on a clean Fedora Rawhide installation, which shows that it isn't limited only to my system.

[Bartosz Brachaczek]

Created attachment 104179 [details]
testcase-screenshot

Attaching also a screenshot how the testcase currently renders on my system.

[Tor Arne Vestbø]

This is a Qt bug, in that the default for QFont::defaultFontFamily() changed for 4.8, which may cause this effect in certain situations.

Closing as invalid, please report to Qt.

[Bartosz Brachaczek]

Reported as QTBUG-20973.