Also "session_id = Optional argument that can be used to reuse session_ids between test runs. This can make for faster testing." is mentioned as arguments for:

$sel = WWW::Selenium->new( %args )

In some (old?) documentation here:

http://release.seleniumhq.org/selenium-remote-control/1.0-beta-2/doc/perl/WWW-Selenium.html#element_locators

but not in cpan