Uncaught TypeError: Cannot read property 'query' of undefined

When I clone the project and visit the examples/simple/simple.php there is an immediate exception which stops all JS processing.

Uncaught TypeError: Cannot read property 'query' of undefined simple-view.js:42

Backbone.View.extend.initialize       simple-view.js:42

a.View                                backbone-min.js:1

r                                     backbone-min.js:1

(anonymous function)                  simple.php:82

f.Callbacks.o                         jquery.min.js:2

f.Callbacks.p.fireWith                jquery.min.js:2

e.extend.ready                        jquery.min.js:2

c.addEventListener.B                  jquery.min.js:2

Am I missing something?

Start by reproducing the exception from examples/simple/simple.php and inspect the failing initialization at simple-view.js:42. Trace the undefined value involved in the .query access and confirm the example completes its JavaScript processing without the reported TypeError.

Written by the indexing model from the issue text.