dragger is used before checking against nullptr in gradient-drag.cpp

    if ( dragger->isA( POINT_MG_HANDLE ) || dragger->isA( POINT_MG_TENSOR ) ) return;

    if (add_to_selection) {
        if (!dragger) return;
        if (override) {

https://gitlab.com/inkscape/inkscape/-/blob/master/src/gradient-drag.cpp#L2004-2008