Visual Editor [native tinymce] doesn’t display labels on actions

Actions from the toolbar of the native visual editor [tinymce], such as add media, add [upload] image, or add link, do not display the correct label on any action dialog tabs: instead they display the php short code – thus on “add link” I’m seeing four tabs marked as
#advlink_dlg.general.tab
#advlink_dlg.popup.tab
#advlink_dlg.events_tab
#advlink_dlg.advanced_tab

Note: I am using WP Super Edit but removing it entirely doesn’t affect the issue. This type of display on the tabs is common across all the relevant button actions on the tinymce toolbars. Have for all plugins tried deactivating and deleting files and reinstalling//reactivating without any change.

Is it possible that an orphan “option” from an unused and deactivated plugin is causing this.

Any ideas or suggestions about what might be causing this would be very welcome.

TIA,

Robert