fix crash when 'remove chord' is pressed but there

are no chords

gui.py

@@ -358,6 +358,7 @@ class DocumentWindow(QMainWindow):
         self.window.blockChordComboBox.addItems(list(self.chordDict.keys()))
 
     def removeChordAction(self):
+        if self.window.chordTableView.selectionModel().hasSelection(): # check for selection
             self.updateChords()
         
             row = self.window.chordTableView.selectionModel().currentIndex().row()
@@ -421,6 +422,7 @@ class DocumentWindow(QMainWindow):
         self.window.blockNotesLineEdit.repaint()
 
     def removeBlockAction(self):
+        if self.window.blockTableView.selectionModel().hasSelection(): # check for selection
             self.updateBlocks()
 
             row = self.window.blockTableView.selectionModel().currentIndex().row()