@sbland_splunk Thank you, this did it for me! I also heard back from Support via a ticket with the same response. For my environment, dashboard_html_allow_iframes was set to true and dashboard_html_allow_embeddable_content was set to false by default. So I had to add to my etc\system\local\web.conf the dashboard_html_allow_embeddable_content = true under [settings] and it worked after a restart!
Some other good details from Support:
Based on the description of the case, after reviewing the Splunk documentation for Splunk version 8.0.1, I found out that Splunk has removed some features in version 8.0.x, including
<iframe> and <embed> , please take a look on below link which contains the information about it:
https://docs.splunk.com/Documentation/Splunk/8.0.3/ReleaseNotes/Deprecatedfeatures#Removed_features_in_version_8.0 In the above link it is recommended to use "html_allow_embeddable_content" flag in web.conf instead of <iframe> and <embed> .
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