Source Preview button does not work as expected on Web Content

• Type: Regression Bug
• Status: Closed
• Resolution: Duplicate
• Affects Version/s: Master
• Fix Version/s: None
• Component/s: CKEditor
• Labels: None
• Fix Priority: 3

Steps to Reproduce:

1. Go to Product Menu > Content & Data > Web Content
2. Create a new Basic Web Content by clicking + icon
3. Go to this URL: "http://www.standards-schmandards.com/exhibits/wysiwyg/sampledoc.htm" and copy the sample text
4. Paste the sample text in CKEditor in Web Content
5. Click on Source to view source code
6. Click on the Preview icon next to Source button to view Preview

Expected Result:

• Preview should show source code on Preview modal

Actual Result:

• Preview does not show anything, and iframe is not centered

*Workaround: Edit in Source view before clicking on Preview button

Reproduced on:
Tomcat 9.0.37 + MySQL 5.7
Portal master GIT ID: d6e2cfe8d86cf4ac7aa0f540c028a25e8837c8ae