+ split file extension from descriptive text of file format to avoid that invalid translation breaks file dialog

+ add method to make image view unclosable for user
+ fix possible crash in MeshAlgorithm::GetMeshBorder
+ fix possible crash in MeshAlgorithm::ConnectLines

src/Gui/DlgProjectUtility.cpp

@@ -112,6 +112,7 @@ DlgProjectUtility::DlgProjectUtility(QWidget* parent, Qt::WFlags fl)
   : QDialog(parent, fl), ui(new Ui_DlgProjectUtility)
 {
     ui->setupUi(this);
+    ui->extractSource->setFilter(QString::fromLatin1("%1 (*.fcstd)").arg(tr("Project file")));
 }
 
 /**