Merge pull request #1240 from ispyisail/fix/project-properties-ok-marks-modified

Fix Project properties > OK marking the project modified with no edit

sources/ui/titleblockpropertieswidget.cpp

@@ -168,6 +168,7 @@ void TitleBlockPropertiesWidget::setProperties(
 	// Show the saved custom values, plus any of the template's custom variables
 	// that aren't defined yet, so the user only fills in the missing ones (#271).
 	DiagramContext context = properties.context;
+	m_context_keys = context.keys();
 	addTemplateVariables(context, index);
 	m_dcw -> setContext(context);
 }
@@ -217,6 +218,14 @@ TitleBlockProperties TitleBlockPropertiesWidget::properties() const
 	}
 
 	prop.context = m_dcw -> context();
+		//The template's custom variables are only offered for filling in
+		//(#271): one left empty is not part of the properties.
+	const QList<QString> keys = prop.context.keys();
+	for (const QString &key : keys) {
+		if (!m_context_keys.contains(key)
+				&& prop.context.value(key).toString().isEmpty())
+			prop.context.remove(key);
+	}
 
 		//The combo box cannot show "no folio numbering": it shows its
 		//placeholder entry, or the project's first numbering. Return what