To quote the wiki page, "You may use this code without any warranty. "

The code is from 2011, when Qt 4 was the latest. Attempting to compile the Git code with Qt 5 or 6 will not work as-is. The error in DocumentWindow::winEvent() is simply because Qt5 changed the API and removed QPaintDevice::winEvent() (and by inheritance from QWidget and QMainWindow). Look at QWidget::nativeEvent() when you are porting.

There are a few typos in the Wiki page source code and a now broken link to the source on Gitorious.
Gitorious ceased to be in 2015 when taken over by Gitlab. The source still exists there. The simple typos are not present in the Git sources.

When you have finished porting to Qt5 and Qt6 feel free to update the wiki page with code that uses include guards to handle version differences.

@dldd the old wiki was a CC license, so that should still apply.
Not sure how that works for code snippets though.

I'll have to edit the template to include a note on that.

Thanks for sharing the bug report link. This may help others to monitor and vote teh issue.
I have also added a couple of tags to your post.

@Wieland ok, then I'll secretly add you to the admin list one day, when I forget that you didn't want to be there. Or tell me when you feel more at home, and I'll add rights :)

The translations have been done at different times and might not have been updated when the original has been updated.