If I open a new window in a browser, from the same computer I opened the last one, will it set up a new empty $_SESSION or will it use the one created by the last script I ran on this computer? Of-course both browser windows are running the same script..
If not, how can I do that?
If I work on two different browsers, will they share the session?
Thanks
New Windows (or Tabs) will use the same session.
You can prevent this by using the ‘Private browsing’ or ‘Incognito’ mode in newer Browsers. This will get you a fresh environment every time.
If you are on OSX, I can recommend Stainless (http://www.stainlessapp.com/) which uses the webkit engine and handles individual sessions within different tabs (See application preferences)