This is in reference to post https://salesforce.stackexchange.com/questions/226338/how-to-show-exception-message-in-lightning-without-stacktrace/226381#226381
Here I am attaching the zip file containing all the metadata that you can deploy to org and reproduce the problem.
- Download the zip file.
- Deploy the zip file to your developer edition org
- Find a account which has only one Opportunity.
- Update Account Id in OpportunityTrigger.trigger and update Opportunity Id in TestAppController.cls
- Edit Account page layout in lightning experience and add HelloWorld.cmp to the layout.
- Save the layout.
- Once layout is saved, go to the layout and click on delete button as I am doing in this video: https://vimeo.com/281628694