Where are the files for the web viewer located?

I want to find out where the files for the web viewer are stored. They are not stored in the vault itself, but are still somehow associated with a specific vault.

It would be great if the files for the web viewer could be stored within the vault itself, so that they would be synchronized automatically.

As leaves (tabs) they would be synced with the workspace still.
Otherwise, you could bookmark them.

There is no way to know what you want to know, btw.