remove the canvas context menu

The middle-click context menu (crosshair toggle, copy as PNG/SVG)
duplicated functionality that is now reachable elsewhere: the
crosshair is toggled by its own toolbar button and the PNG/SVG
clipboard copies get dedicated toolbar buttons. Removing it frees the
middle mouse button on the plot canvas.

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

src/damaris/gui/DamarisGUI.py

@@ -3270,9 +3270,6 @@ class MonitorWidgets:
         # add figure to canvas
         self.matplot_canvas = BlitSafeCanvas( self.matplot_figure )
 
-        # add ctrl + right-click context menu to canvas
-        self.matplot_canvas.connect("button-press-event", self.on_canvas_button_press)
-
         self.display_table = self.xml_gui.get_object( "display_table" )
         self.display_table.attach( self.matplot_canvas, 0, 6, 0, 1, gtk.AttachOptions.EXPAND | gtk.AttachOptions.FILL, gtk.AttachOptions.EXPAND | gtk.AttachOptions.FILL, 0, 0 )
         self.matplot_canvas.show( )
@@ -3825,40 +3822,6 @@ class MonitorWidgets:
                 self.matplot_cursor = None
                 self.matplot_canvas.draw()
 
-    def on_canvas_button_press(self, widget, event):
-        """Handle button press events on matplotlib canvas"""
-        if event.button == 2:  # middle click
-            self.show_canvas_context_menu(event)
-            return True
-        return False
-
-    def show_canvas_context_menu(self, event):
-        """Show context menu for matplotlib canvas"""
-        menu = gtk.Menu()
-
-        # toggle cursor
-        toggle_cursor = gtk.CheckMenuItem(label="Crosshair")
-        # Set the current state based on whether cursor exists
-        if hasattr(self, 'matplot_cursor') and self.matplot_cursor is not None:
-            toggle_cursor.set_active(True)
-        else:
-            toggle_cursor.set_active(False)
-        toggle_cursor.connect("toggled", lambda w: self.matplot_cursor_button.set_active(w.get_active()))
-        menu.append(toggle_cursor)
-
-        # Copy as PNG
-        item_copy_png = gtk.MenuItem(label="Copy as PNG")
-        item_copy_png.connect("activate", self.copy_canvas_as_png)
-        menu.append(item_copy_png)
-
-        # Copy as SVG
-        item_copy_svg = gtk.MenuItem(label="Copy as SVG")
-        item_copy_svg.connect("activate", self.copy_canvas_as_svg)
-        menu.append(item_copy_svg)
-
-        menu.show_all()
-        menu.popup_at_pointer(event)
-
     def copy_canvas_as_png(self, widget):
         """Copy canvas to clipboard as PNG"""
         self.copy_display_data_to_clipboard(widget)