I was just curious if WordPress was adding anything during the switching process.
Does this still happen if you take the <iframe> element out temporarily?
Looking into this more, I’m not sure if it’s possible to prevent, as WordPress adds the paragraphs when the content is output. That being said, I’ve only seen this happen when shortcodes are being used, usually.
As I am telling you, it is not WP!!. It is GeneratePress Sections Module that creates that problem and that is why I need your help.
If instead of using GeneratePress Sections Module I use WP HTML block then it works ok.
I should be able of writing html with GeneratePress Sections Module just like I do in normal WP HTML block.