Currently, access to the URL used to test the Remex + Electron based book rendering workflow (Special:RenderBook/test) is unrestricted.
== Context
The original conversation between @Jdlrobson and @Tgr starts here: T175868#3680538
== AC
[] Restrict access to the special page to the Readers Web/Infra engineers and PO (@ovasileva)
== Solutions
1. @Tgr submitted [a change](https://gerrit.wikimedia.org/r/#/c/377929/) as part of T175868, which restricts access to the URL to users with `"(WMF)"` in their name
- Per T175868#3681307, you have to be an admin to register names with WMF in 'em
1. In T175868#3686340, @Tgr explained how to create a new group with the `"testpdf"` right.
- This seems a little more involved but superior to the above in that it provides finer grained access control. OTOH, do we really need that?
1. In T178289#3688851, @Jdlrobson suggested that we should simply disable the testing URL until we're ready to test the concatenation feature
1. Move the logic from @Tgr's change to the Collection extension (a hybrid of @Tgr's [[ https://gerrit.wikimedia.org/r/#/c/377929/ | change ]] and @Jdlrobson's [[ https://gerrit.wikimedia.org/r/384601 | change ]])