Embed iframe into team site

[Tom Robey]

When pasting the embed code into the embed webpart I receive a message saying I need to add it to HTML Field Security.  However, I'm not able to find that as an option under Site Collection Administration for the specific team site I'm working with.   However, if I go to site settings for our main sharepoint site its there.  I have added the web address as indicated in the error message but it still does not work.   Is there a delay when adding a site like this?   Or is this a Microsoft oversight?  It tried to embed a PowerApp as well and that didn't work, and added PowerApp.com to the HTML field security and that didn't work either.   I have scripting enabled if that makes a difference.  Any assistance would be appreciated.  

[#2 · Accepted solution]

From another post on here:

Connect to sharepoint online powershell:

connect-sposervice -url https://YourTenant-admin.sharepoint.com

set-sposite https://yourTenant.sharepoint.com/sites/GroupSiteUrl -DenyAddAndCustomizePages $false

Then, navigate directly to the settings page for the group and you will see the 'HTML Field Security' option which you can modify:

https://yourTenant.sharepoint.com/sites/GroupSiteUrl/_layouts/settings.aspx

You will have to be an owner of the group to be able to see the settings page.

[#3]

Well I did it.  I followed the PowerShell commands as you suggested and it worked like a charm.  My past experience with PowerShell has not been as successful.  Thank you.