GUI: log_window: Try to choose monospace font in a more portable way

gui/QT/ui/log_window.ui

@@ -86,11 +86,6 @@
        </disabled>
       </palette>
      </property>
-     <property name="font">
-      <font>
-       <family>Monospace</family>
-      </font>
-     </property>
      <property name="placeholderText">
       <string/>
      </property>

gui/QT/window/log_window.cpp

@@ -1,6 +1,8 @@
 #include <QClipboard>
 #include <QFileDialog>
 #include <QFile>
+#include <QFont>
+#include <QFontDatabase>
 #include <QTextStream>
 #include <QtGlobal>
 #include "log_window.hpp"
@@ -17,6 +19,9 @@ LogWindow::LogWindow(QWidget *parent): QDialog(parent){
 #else
 	ui.terminal->setTabStopDistance(40);
 #endif
+	const QFont fixedFont = QFontDatabase::systemFont(QFontDatabase::FixedFont);
+	ui.terminal->setFont(fixedFont);
+
 
 	connect(ui.copyBtn, SIGNAL(clicked()), this, SLOT(copyToClipboard()));
 	connect(ui.saveBtn, SIGNAL(clicked()), this, SLOT(saveToFile()));