As part of my work, I often use PhpMyAdmin, though after I use PhpMyAdmin, I do some work on the script, then I return to PhpMyAdmin to add some SQL, and then I get the session has expired message, and I lose the changes. It is so frustrating. The best thing is to edit the configurations and extend the login cookie session if you have access to the PhpMyAdmin scripts on the server.
Main:
Navigate to PhpMyAdmin root directory and find config.inc.php , edit the file, then search in the file for “LoginCookieValidity”, if you found one, change the value after the equal sign to the amount of SECONDS for the session to last. if you didn’t find it, then add the following line after any $cfg line, in a separate blank line:
$cfg[‘LoginCookieValidity’]=60 * 60 * 10;
Obviously 60 seconds , 60 minutes , 10 hours . or you can make the value : 3600 * 10 , or 36000 seconds .
If you have no access to PhpMyAdmin scripts, then you have to live with it unfortunately, but what can you do to avoid losing your current page after leaving it for some minutes, right click on any non-dangerous link (; in PhpMyAdmin page and open it in new page, in that new page, enter your username and password, then return to your current page, sometimes though especially when your current page before expiration is insert page with some data, what you do then is just copy paste the data into your fresh login.