I built the smallest app exposing a curious behaviour wiht js managing in a ruby app : On the main screnn, I design a button with an onclick js function that modifies html in a div. No problem with that screen.
I create a small model. On the main screen, I put a link to the index action of the new controller. There's the curious sequence :

Launch the app
Click on button : it works
Click on the link
On the new page, click on Home
Click on buttton : again : it doesn't work !

When you look in the source debugging js on the fly, one can see that the html have been modified, but not in the document displayed.

Here's the link to my app in github https://github.com/jmarzin/essai_js_rhomobile