[REG 5 → 6] Default context menu is missing icons

When right clicking in e.g. simplebrowser on Qt 5, some menu items have icons:

but not with Qt 6:

This is most likely due to: Move styled icons from page to view (Ica7b1688) · Gerrit Code Review: It introduces a new QWebEngineViewPrivate::webActionIcon where the code is moved to, but that code doesn't get called from anywhere at all.