Thanks for this jota.
The content is fine. The app is fine. I have another WP site without bitnami which is fine. It happily allows iframes. The issue is: my bitnami wp site in its default configuration refuses to display content in an iframe in an external site. I deleted and re-installed WP, there are no plugins, no previous configurations. It's not working.
You refer to previous advice which says to check WP_HOME and SITE_URL but not for multisite.
I'll skip that shall I?
Then it says 'change the ALLOW FROM line in wp-config'. As I said, there is no such line in my wp-config file.
Should I insert ALLOW FROM "https://your_domain.com"?
If so, where - above or below the 'that's all stop editing' line?
Does that matter?
Should your_domain include the subdomain?
Then it says ALLOW FROM is deprecated.
Should I not insert it then?
Then it says 'insert the 'SAMEORIGIN' line'
Should I do that then?
And if so, into which file, and where?
And will that actually help things, considering the error message I quoted?
Your next suggestion is to configure them in the wp-config. Not sure who them is, and this is less than specific.
Your next suggestion is to configure them in the WP dashboard. That's even more than less than specific
How do I do that?
I don't mean to sound ungrateful but I there's no great sense of progress around this yet.