The same error message as in T108876
1. Open 'Summarize' for a topic
2. Open 'Reply' for the same topic.
3. Click 'Cancel' for 'Reply'
4. Click 'Cancel' for 'Summarize' - Console displays the error.
Steps #3 and #4 if are done in reverse order do not produce the error.
```
Uncaught TypeError: Cannot read property 'commandRegistry' of null
ve.ui.Tool.getCommand @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:456
ve.ui.Tool.onUpdateState @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:455mw.loader.implement.oo.EventEmitter.emit @ VM6518:169
ve.ui.Toolbar.updateToolState @
load.php?debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:459
ve.ui.Toolbar.onContextChange @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:458mw.loader.implement.oo.EventEmitter.emit @
VM6518:169ve.dm.Surface.stopQueueingContextChanges @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:130
ve.dm.Surface.changeInternal @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:134ve.dm.Surface.change @ load.php?debug=false&lang=en&modules=ext.visualEditor.core|oojs-
ui.styles.icons-editing-advanced&sk…:133
ve.ce.Surface.changeModel @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:394ve.ce.Surface.onSurfaceObserverRangeChange @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:368mw.loader.implement.oo.EventEmitter.emit @
VM6518:169
ve.ce.SurfaceObserver.pollOnceInternal @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:397
ve.ce.SurfaceObserver.pollOnce @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:396
ve.ce.Surface.onDocumentBlur @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:337
ve.ce.Surface.onFocusChange @ load.php?
debug=false&lang=en&modules=ext.visualEditor.core|oojs-ui.styles.icons-editing-
advanced&sk…:335OO.ui.debounce.later
```