Previous fixes for this issue are reported&fixed in {T108876} and {T109750}
The issue seems to be specific to exact steps that described below - Reply and then try to post a new topic(not for two replies or two new topics in a row).
1. Click on Reply - make sure that VE mode is selected.
2. Enter some text and click 'Reply' to save.
3. Click on 'Start a new topic' - make sure that the CE is in VE mode
4. As soon as you click in CE field - the following error is displayed:
```
Uncaught TypeError: Cannot read property 'commandRegistry' of null
ve.ui.Tool.getCommand
ve.ui.Tool.onUpdateState
ve.ui.AnnotationTool.onUpdateState
oo.EventEmitter.emit
ve.ui.Toolbar.updateToolState
ve.ui.Toolbar.onContextChange
oo.EventEmitter.emit
ve.dm.Surface.stopQueueingContextChanges
ve.dm.Surface.changeInternal
ve.dm.Surface.change
ve.ce.Surface.changeModel
ve.ce.Surface.handleObservedChanges
ve.ce.SurfaceObserver.pollOnceInternal
ve.ce.SurfaceObserver.pollOnceSelection
ve.ce.Surface.onDocumentSelectionChange
jQuery.event.dispatch
elemData.handle
```