Qt restoring geometry incorrectly on X11

Question

I'm using Qt 4.8.4 on Xorg 1.13.1. I'm saving the window geometry in the same way suggested in the documentation:

QSettings settings;
QByteArray geom = widget->saveGeometry();
settings.setValue("widget_geometry", geom);

Also restoring on startup:

QSettings settings;
QByteArray geom = settings.value(buf).toByteArray();
widget->restoreGeometry(geom);

The problem I'm facing is that the window isn't placed in the same position as it was saved. The size is fine. Depending on which window manager I use, the results are different.

• In i3, the window is one pixel off on both axes, presumably to make up for the window border.

• In Unity (mutter?), no matter where I put the window, it gets nudged over 10 pixels every time it is restored. It also seems to have a y-limit, but I can live with that since it's consistent.

• In fluxbox, the window is restored to its saved size and position.

I've done a bit of digging and deconstructed the byte array that is saved into the settings file. I've tried manually adjusting the position of the window instead of using restoreGeometry(), but there's really no way for the application to know what kind of WM inconsistencies it's dealing with. In some WMs, setting the position using the frame geometry instead of the normal geometry works, but screws up other ones. I've read from the Qt geometry documentation that you can't really count on any kind of consistency from X11 window managers, so I'm out of ideas. I'm just hoping some clever person out there has solved this!