How to restart Chrome without losing your open tabs
To restart Google Chrome without losing your open tabs just type chrome://restart into the address bar and press Enter. However, do not do this if you have Chrome set up to restore a previous session upon restart, otherwise you may find the browser attempts to reload a tab containing ‘chrome://restart’, putting you in an infinite loop of restarting.
If this happens, try editing the Chrome shortcut and adding --disable-restore-session-state to the target entry. Also see: Top 10 Google Chrome tips and tricks.
How to restart Firefox without losing your open tabs
To restart Firefox without losing your open tabs press Shift-F2 and then type restart into the console window before pressing Enter.
How to restart Internet Explorer without losing your open tabs
To restart Internet Explorer without losing your open tabs, close the application and relaunch it, then select Tools > Reopen previous browsing session. Unfortunately, this will restore the tabs on your last Internet Explorer window, but it won’t reopen multiple windows if you had them open.