I've been trying to install the Math extension to no avail. From https://lists.wikimedia.org/pipermail/mediawiki-l/2018-March/047266.html, I should only need to copy the Math extension files into the proper extensions directory. In this case, formulas are rendered as pure text; nothing happens; so, can't get installation "out of the box."
When I add "wfLoadExtension( 'Math' );" to the LocalSettings.php file, I instead get the error: 'Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":).'
php-curl is installed; not sure what else I can try. Thanks in advance.