regression - Javascript error when discarding component changes in the channel-manager component sidebar

Verified to be working in 14.2.2. Failure reproduced in 14.3 and saas branches

1. Start project with component properties sidepanel (here hap-community)
2. Go to home page and add Banner component. Set banner field. (don't save or discard)
3. Click on Xmas tree document and click Edit content
4. Dialog opens to discard/save changes. Select Discard

Expected: Banner side panel closes and changes discarded, xmas tree document component properties open.

Actual

Error occurred while closing the ComponentEditor -> TypeError: Cannot read property 'getId' of null
at Gn.open (componentEditor.service.js:68)
at Gn.reopen (componentEditor.service.js:361)
at Gn.discardChanges (componentEditor.service.js:357)
at componentEditor.service.js:406
at angular.js:17948
at angular.js:17996
at u.$digest (angular.js:19114)
at angular.js:19435
at Vr.completeTask (angular.js:21234)
at angular.js:6814

 After this the browser must be reloaded to continue working

In the saas branch also seen this error:

Wicket.Ajax: Wicket.Ajax.Call.processComponent: Component with id [[id83]] was not found while trying to perform markup update. Make sure you called component.setOutputMarkupId(true) on the component whose markup you are trying to update.