Going offline

[Erik Walter]

Is there an easy way to tell Mozilla to be in offline mode.  I basically 
want it to NEVER access the network when loading a document. 
Unfortunately with Javascript and other CSS stuff, it's sometime 
possible to have an HTML document that appears to be all local in the 
DOM, but actually contains remote resources (i.e. if you have a CSS 
style that sets a remote resource for the background image).  We 
recreate a document on multiple machines and some may or may not have 
network access, but it's important that they all look alike (regardless 
of network connectivity).  The only way (I can think of) to do this is 
to force all clients to be offline.

Is this a preference I can set?  And is there a page somewhere that 
lists the preferences that are available programmatically?