This issue was really hard to debug: first, I was able to reproduce it only in production
environment, not in development env. It's still unclear how it affects Internet
Explorer's behaviour.
As it turned out, IE caches every ajax requests. It means that e.g. on the
deployments#show page clicking on the Properties tab, then the Instances tab and then back
to the Properties tab does not fire any request to the server to update the content of the
Properties tab. Needless to say that it's not broken in FF or Chrome.
The solution is quite simple, jQuery provides a 'cache' parameter for the global
ajaxSetup config. If it's false, then jQuery will append a timestamp to the url
avoiding the IE browser cache.