Taken from jQuery's codebase. https://stackoverflow.com/questions/19669786/check-if-element-is-visible-in-dom
To install WWW::WebKit2, copy and paste the appropriate command in to your terminal.
cpanm
cpanm WWW::WebKit2
CPAN shell
perl -MCPAN -e shell install WWW::WebKit2
For more information on module installation, please visit the detailed CPAN module installation guide.