I'm having the same problem. I am on a domain with server 2008 R2 roaming profile. Clients vary from XP to 8. Seems to disable on a per profile bases.

I think my situation is the same, but I am running win 7

Same problem as well, Win7x64 on domain.

There appears to be a problem with Firefox 20 with UNC paths when using roaming profiles on a server.

• [/questions/955140] why is the 20.0 address bar unresponsive?

This is currently investigated and tracked via this bug report.

• bug 857672 - Address Bar not working (roaming profiles;UNC path support OS.File)

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