Well, they can simply embed the static resources in the PHP file itself, why not?

Or even simpler just download the JS and put it next to the script if single file isn't a hard requirement (which I don't see a use case for besides simplicity)

> which I don't see a use case for besides simplicity

There is a use case for that. Maintainability. Drop one file to start. To delete, delete the file. To upgrade, replace the file.

For example, I really like tiddlywiki because no matter where or what, I only have to deal with and track 1 file.

It’s impressive what they’ve accomplished with just one file full of custom content. Even upgrading is possible.

I suppose? Replace "file" with "non nested folder" and you get the same result. An html doc + 2-3 javascript files isn't a nightmare to deal with.

Yeah. There are easy tools to use to automate it as well if they're relying on it to be updateable from other JS build tools and so on.