Adapt the error screen of Tor Connection to the actual failure mode

We identified 5 different cases for the error screen:

  • Case #1 (Hiding): Time sync + Captive portal + Proxy + Bridge

    I think that the current error screen and flow are fine.

  • Case #2 (Autoconnect + captive portal): #5785 (closed)

  • Case #3 (Autoconnect + blocked): Bridge only: #19171 (closed)

    Here we should explain a bit more what is happening below the title "Error connecting to Tor" and reuse the improvements from case #2.

    This screen would be:

    Error connecting to Tor
    =======================
    
    This local network seems to be blocking access to Tor.
    
    * Tor bridge by email
    
      Tor bridges are secret Tor relays. Use a bridge as your first Tor relay if connections to Tor are blocked, for 
      example in some countries, by some public networks, or by some parental controls.
    
      To get a bridge, send an empty email to...
    
  • Case #4 (Autoconnect + failed time sync but not captive portals): Time sync only

    Case #4 is bug, censorship, or network issue in our time sync.

    Here again we should explain a bit more what is happening.

    Also, should we skip the error screen and go straight to the clock configuration screen? See also #21475 (where we might change the clock configuration popups into proper screens) and #21476 (where we propose to skip the error screen when bridges are the only solution).

    Error connecting to Tor
    =======================
    
    Tails failed to fix the clock of your computer.
    
    * Wrong clock
    
    ...
    
  • Case #4.2 (Autoconnect + failed time sync but not captive portal + Tor blocked): Time sync + Bridge

    Case #4.2 is Case #4 + default bridges not working = stronger suspicion of censorship (or wrong time zone configured).

    Here again we should explain a bit more what is happening.

    Error connecting to Tor
    =======================
    
    Tails failed to fix the clock of your computer and this local network seems to be blocking access to Tor.
    
    * Wrong clock
    
    ...
    
    
Edited by sajolida