# Prototype not working with rails 2.2.2?

**URL:** <https://www.ruby-forum.com/t/prototype-not-working-with-rails-2-2-2/158913>\
**Category:** Rails\
**Created:** [January 29, 2009, 11:06am UTC](https://www.ruby-forum.com/t/prototype-not-working-with-rails-2-2-2/158913 "2009-01-29T11:06:59Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![riky](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/94ad74/32.png) [@riky](https://www.ruby-forum.com/u/riky)\
**Post date:** [January 29, 2009, 11:06am UTC](https://www.ruby-forum.com/t/prototype-not-working-with-rails-2-2-2/158913/1 "2009-01-29T11:06:59Z")

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Hi,

i made an application using rails and prototype and all worked fine…  
But today i upgraded rails to 2.2.2 and from that moment when i open  
the webpage with firefox it gives me an error like “object is null”  
and some prototype “helpers” doesn’t work at all as for example the  
observe\_field…

Can anyone help me?

Thanks,  
Riccardo