Iron Browser as default in Ubuntu 14.04

[Valonqar]

Hello everybody!
A simple problem: i can't set Iron browser as default in my Ubuntu 14.04. I've tried to run it with admin privileges but here's the message

Code: Select all

mario@mario-X550CL:~$ sudo /usr/share/iron/iron 
[0208/123347:ERROR:nss_util.cc(96)] Failed to create /home/mario/.pki/nssdb directory.
[0208/123347:FATAL:chrome_main_delegate.cc(382)] Check failed: process_type.empty(). Unable to get the user data directory for process type: zygote
#0 0x5629977056de base::debug::StackTrace::StackTrace()
#1 0x562997717ecb logging::LogMessage::~LogMessage()
#2 0x5629972c6a8c ChromeMainDelegate::PreSandboxStartup()
#3 0x5629976cc34d content::ContentMainRunnerImpl::Initialize()
#4 0x5629976cb57a content::ContentMain()
#5 0x5629972c6298 ChromeMain
#6 0x7f510ae1aec5 __libc_start_main
#7 0x5629972c6159 <unknown>

and the browser never opens.
I've also tried adding a new option in update-alternatives:

Code: Select all

mario@mario-X550CL:~$ sudo update-alternatives --config x-www-browser 

  Selezione    Percorso              Priorità  Stato
------------------------------------------------------------
  0            /usr/share/iron/iron   100       modalità automatica
  1            /usr/bin/firefox       40        modalità manuale
* 2            /usr/share/iron/iron   100       modalità manuale

but still nothing.