Why Next-Gen formats do not work with Elementor
In some cases, you might not be able to see Next-Gen images when using the tag method and Elementor as your page builder.
There are a few main reasons for this.
Elementor’s gallery module
If you use this a lot, it would be ideal to use rewrite rules method for delivering Next-Gen formats (unless you use Cloudflare/CDN, as it would not work in that case).
Elementor thumbs
When adding a content in Elementor, there is possibility to add thumbnails to sections. These are then moved to specific folder inside wp-content and Imagify will not optimize these by default. Hence there won’t be Next-Gen images present for these as well.
The easiest way to check this is to check the source code of your pages and look for:
If you see this, make sure to go to Imagify Settings and add this folder as a custom folder so these images are getting optimized.
You might need to optimize the existing ones in order to apply optimization and Next-Gen creation. You can do this via Media > Other Media