qt5: Use the fixed font the system recommends

Github-Pull: #7214
Rebased-From: fa2f4bc4eb0f21f5be8c88954ae2d99c5b18b987

src/qt/guiutil.cpp

@@ -62,6 +62,10 @@
 #include <QUrlQuery>
 #endif
 
+#if QT_VERSION >= 0x50200
+#include <QFontDatabase>
+#endif
+
 #if BOOST_FILESYSTEM_VERSION >= 3
 static boost::filesystem::detail::utf8_codecvt_facet utf8;
 #endif
@@ -90,6 +94,9 @@ QString dateTimeStr(qint64 nTime)
 
 QFont fixedPitchFont()
 {
+#if QT_VERSION >= 0x50200
+    return QFontDatabase::systemFont(QFontDatabase::FixedFont);
+#else
     QFont font("Monospace");
 #if QT_VERSION >= 0x040800
     font.setStyleHint(QFont::Monospace);
@@ -97,6 +104,7 @@ QFont fixedPitchFont()
     font.setStyleHint(QFont::TypeWriter);
 #endif
     return font;
+#endif
 }
 
 void setupAddressWidget(QValidatedLineEdit *widget, QWidget *parent)