Support older KF5 versions

src/worksheet.cpp

@@ -37,6 +37,7 @@
 #include <QTimer>
 #include <QXmlQuery>
 
+#include <kcoreaddons_version.h>
 #include <KMessageBox>
 #include <KActionCollection>
 #include <KFontAction>
@@ -2066,7 +2067,11 @@ void Worksheet::initActions()
     // Font Family
     m_fontAction = new KFontAction(i18nc("@action", "&Font"), m_collection);
     m_richTextActionList.append(m_fontAction);
+#if KCOREADDONS_VERSION >= QT_VERSION_CHECK(5, 78, 0)
     connect(m_fontAction, &KFontAction::textTriggered, this, &Worksheet::setFontFamily);
+#else
+    connect(m_fontAction, QOverload<const QString&>::of(&KFontAction::triggered), this, &Worksheet::setFontFamily);
+#endif
 
     // Font Size
     m_fontSizeAction = new KFontSizeAction(i18nc("@action", "Font &Size"), m_collection);