The real fix is to change #if QT_VERSION < QT_VERSION_CHECK(5, 13, 0) to

to #if QTWEBENGINEWIDGETS_VERSION < QT_VERSION_CHECK(5, 13, 0)

This problem is that freesbd doesn't build qtwebengine 5.13 with qt 5.13
but it uses directly qt5.12.

Revert "Revert "Port some deprecated methods""

This reverts commit 601cf0ecfc207e65a35c89933c7b4008bd59812c.