There is an issue on doing the document window context menu customization in toolbar/menu mode resulting in customization is not saved on closing the Customize dialog window. The workaround is as follows:

1. Switch the user interface to ribbon mode. Exit UltraEdit and start it again now in ribbon mode.
   It is important to restart UltraEdit after switching from toolbar/menu mode to the ribbon mode!
2. Right click into the document window of the active file and click on last item Customize…
3. Select the category File on left side of the Customize dialog window and search on right side for the command Sort file (using current options). There can be also searched for the command Advanced sort/options… if the Advanced Sort/Options dialog window should be always opened first before doing a sort.
4. Drag and drop this command into the document context menu displayed left to the Customize dialog window.
   Please note the black line displayed on moving the mouse pointer over the context menu indicating the inserting position.
5. Click on button Close in the Customize dialog window.
6. Exit UltraEdit and start it again. Switch back to toolbar/menu mode with either contemporary or traditional menus.

The command to sort the file respectively the current selection is now in the document window context menu.

It is advisable to save the modified user interface as a custom layout. Open the Layout Manager dialog window by clicking in ribbon mode on ribbon tab Layout on first item Layout or in toolbar/menu mode with contemporary menus in menu Layout in submenu Layout on menu item Manage layouts or in toolbar/menu mode with traditional menus in menu View in submenu Layouts on menu item Manage layouts… Use the button Save current state as… and enter a name for the customized layout like My Layout.