Website does not load in Visual Editor Composer, if X-Frame-Options is received as a header in Target call response. A related error would also be displayed in browser's console.
Follow the steps as mentioned below:
1. If issues occur in the Enhanced Experience Composer and you not able to load the website on Target, try turning off the Enhanced Experience Composer and use the Visual Experience Composer instead.
To disable the Enhanced Experience Composer, go to Target > Setup > Preferences and turn off the Enable Enhanced Experience Composer option.
2. If neither the Visual Experience Composer nor the Enhanced Experience Composer works, use a browser extension like Requestly(Chrome) that can overwrite the X-Frames header options for your site and allow them to be loaded in iFrames, enabling the VEC.
3. To use the Requestly extension on Chrome:
a) Turn off the Enhanced Experienced Composer.
b) Install the Requestly browser extension on Chrome.
c) Open the extension and configure it using the following:
1) Select Modify headers.
2) Enter the following:
Toggle Add to Remove.
Toggle Request to Response.
Enter "X-Frame-Options" as the header name.
You should now be able to load the page quickly with the Visual Experience Composer.