You can read about pagination here, and base layouts here.
My guess for the empty with block is that it is being used as a placeholder in the base template, to be overridden in the index layout. But that is just my guess. My suggestion would be to ask the author directly, as it is their code.
Hi, I made the template you are referencing. I used a preload block to force loading the shortcodes that will appear on a page before anything else. This way, shortcodes are able to add CSS and JS files to a .Scratch variable, and I can use this variable to create links to these files in the HTML head. I used the “with” function to load the shortcodes without actually rendering them.
The main reason why I wanted this behaviour is to be able to use the uniq function to avoid duplicating CSS when the same shortcode is included several time in a single page.
If you do not plan to include CSS and JS files with shortcodes, it is totally okay to remove this code!
With the meta-preload the browser loads the page and after it he can load the suggestions. This is no brake in the index page. After following a link to a page using this scripts ot css files, the browser has this information in cache. Depending on the network speeds this can speed up the following ~ (parts of) a second.
My preloaded files have a size of 300k, you can calculate it with your network speed.