There is a Company Branding feature that only works on sign-in only policies. And then there is this UI customization in this article.
Reference: SO Post
I think the differences should be documented...
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@spottedmahn Thanks for the feedback! I have assigned the issue to the content author to investigate further and update the document as appropriate.
Additional data, see Jose's SO answer
@spottedmahn We have opened an item in our documentation backlog to update UI customization information in the article. We'll respond back to you on this issue when we've done the work. For now, we'll close this GitHub issue.
great, thanks @davidmu1