Fix building on Qt6

OpenRGB.pro

@@ -13,6 +13,8 @@ QT +=
 
 greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
 
+greaterThan(QT_MAJOR_VERSION, 5): DEFINES += _QT6
+
 #-----------------------------------------------------------------------------------------------#
 # Application Configuration                                                                     #
 #-----------------------------------------------------------------------------------------------#
@@ -445,7 +447,7 @@ SOURCES +=
     Controllers/FanBusController/RGBController_FanBus.cpp                                       \
     Controllers/GainwardGPUController/GainwardGPUController.cpp                                 \
     Controllers/GainwardGPUController/GainwardGPUControllerDetect.cpp                           \
-    Controllers/GainwardGPUController/RGBController_GainwardGPU.cpp                             \    
+    Controllers/GainwardGPUController/RGBController_GainwardGPU.cpp                             \
     Controllers/GalaxGPUController/GalaxGPUController.cpp                                       \
     Controllers/GalaxGPUController/GalaxGPUControllerDetect.cpp                                 \
     Controllers/GalaxGPUController/RGBController_GalaxGPU.cpp                                   \

qt/OpenRGBSupportedDevicesPage.cpp

@@ -45,7 +45,11 @@ void OpenRGBSupportedDevicesPage::on_SaveButton_clicked()
 
 void OpenRGBSupportedDevicesPage::on_Filter_textChanged(const QString &arg1)
 {
+#ifdef _QT6
+    detectorSortModel->setFilterRegularExpression(QRegularExpression(arg1 , QRegularExpression::CaseInsensitiveOption));
+#else
     detectorSortModel->setFilterRegExp(QRegExp(arg1, Qt::CaseInsensitive));
+#endif
 }
 
 void OpenRGBSupportedDevicesPage::on_ToggleAllCheckbox_toggled(const bool checked)