PHP Library Dropdown not showing

I have added your plugin to a customer live site, which is on server I do not control, having tested it on a test site on my own VPS. It works fine on my VPS, hence the decision to go live with it.

Having loaded-up the plug-in, I have added all of the settings used on the test site, except one – The first item in General Settings which is the PHP Library dropdown. This is not showing on the live server, so I cannot select the extension needed.

Is this a bug with the plugin, or potentially a server setting on the live server? If the latter, what do I need to get the person controlling the live server to change?

Thanks

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