KScreen::Config::current can return null

core/utils.cpp

@@ -100,6 +100,7 @@ QSizeF Utils::realDpi(QWidget* widgetOnScreen)
         // Firstly try to retrieve DPI via LibKScreen
 #if HAVE_LIBKSCREEN
         KScreen::Config* config = KScreen::Config::current();
+        if (config) {
             KScreen::OutputList outputs = config->outputs();
             QPoint globalPos = widgetOnScreen->parentWidget() ?
                         widgetOnScreen->mapToGlobal(widgetOnScreen->pos()):
@@ -136,6 +137,7 @@ QSizeF Utils::realDpi(QWidget* widgetOnScreen)
                     return res;
                 }
             }
+        }
 #endif
     }
     // this is also fallback for LibKScreen branch if KScreen::Output