Advanced iframe 7.6 is available now in the pro and the free version!
A lot of improvements made it to this release. See here for details:
The most interesting thing is the cookie support inside the iframe! I have included all known solutions for this.
Also the standalone version was optimized and does now work in Joomla!
Optimized Gutenberg support is planned for 7.6.1 !
Have fun using Advanced iframe,