Symptoms

Open an Service Portal page in the Page Designer. 

1) When editing a widget by clicking the "pencil" button, the widget instance does not load and the page is frozen. 

2) Observe errors in the system log
"SPWidget:SCSS portalId is null (id: vfd1f4ec347730200ba13a5554ee490c0 portalId: null): no thrown error"

Release

Only tested in Madrid

Cause

There are widget instances on the Service Portal page which do not have an associated widget. 

The widget instance records are corrupted. 

Resolution

Removing the widget instances record.