Hello Everyone,
Yes. I searched high and low for the answer but, there is no definite solution?
My site serves both https and http however, depending on the browser used "mixed" content is blocked with https, or several warnings appear if the site is visited with just http.
Example:
You should not enter any sensitive information in this site (for example password...)
How can someone log in reliably with these messages poping up?
Anyway, I am not sure how to achieve this for you but, it's possible to use
Let's Encrypt with a wild card certificate at two (or more) levels
*.n##.nabble.com
*.nabble.com
Sure, it won't do anything for custom domains however, it would work just fine for standard embedding.
Searching for a possible solution I was inspired by a few topics: