While testing the Timeline API I noticed that a number of HTML tags are not accepted by the Mirror API and if so are removed from the created timeline. I did not see a list of accepted tags or denied tags anywhere in the API and the non-authenticated playground is misleading as it allows the developer to make false assumptions about what is and is not allowed in the timeline.
So my question is simply: What tags are allowed and what is unavailable?
See this post here:
Are there any restrictions for using HTML tags in "html" field?
We'll get it into the documentation very soon.