"Show email details" button doesn't behave as expected when multiple activity streams exist on a form

Clicking the "Show email details" button causes unexpected behavior if multiple activity streams exist on the same form. Instead of the iframe being pointed at a page containing the content of the email, the iframe is pointed at a URL that doesn't exist on the instance. For example:

https://helsinkipatch6.service-now.com/%7B%7B::emailBodySrc%7D%7D

Behavior across instances in dealing with a URL like this varies. Some instances will show a "Page not found" error. Other instances will accept the URL and load /navpage.do in the iframe, which then redirects the page you're on back to the user's homepage.

 

1. Log on to the instance as a maint user.

2. Navigate to Incident > Open.

3. Open INC0000055 - "SAP Sales app is not accessible".

4. Right-click in the form header, and choose Configure > Form Layout.

5. Add the Activities (filtered) element into the first section of the form (Incident) and click Save.

6. Click the three-dot "More options" icon in the form header and click Email.

7. Add some text in the Compose Email window and click the Send button.

8. Navigate to System Logs > Emails.

9. In list view, find the email you just sent in the list, and change its type is "sent" rather than "send-ready".

10. Navigate to Incident > Open.

11. Open the incident (for example, INC0000055 - "SAP Sales app is not accessible").

12. In the activity stream in the email record, click the Show email details link.

    Instead of an iframe appearing that shows the body of the email directly below the "Show email details" link, the iframe tries to load the following URL on the instance:
    /%7B%7B::emailBodySrc%7D%7D

    The following JavaScript error occurs in the browser console:
    TypeError: Cannot read property 'displayValue' of undefined.

    The error occurs because the JavaScript object containing the details of the activity stream contains no values inside the email property.

There is no workaround. The system is not designed to support multiple occurrences of activity streams on the same form.