Due to the major breaking changes set to be introduced with the Gutenberg editor in WordPress v5.0, NextGEN Gallery Optimizer has now been discontinued.
Valid license holders for Optimizer Pro will continue to receive support if required, but the product has now been removed from sale, in preparation for the release.
I want to say a big thank you to everyone who's enjoyed using the plugin to optimize their sites over the last six and a half years, and wish you all the best for the future.
Optimizer’s NextGEN Gallery Deactivator substantially improves your site's page load speed on non-gallery pages, by excluding all of NextGEN's PHP code from being processed on the front-end of your site (except on pages you specify).
Have a page called "Gallery", perhaps? Simply enter it into the settings page, and it's the only place NextGEN will ever load outside the admin.
To test how effective Deactivator is, simply manually deactivate NextGEN on your Plugins page, and browse a few non-gallery pages on your site. Feel the difference? That's exactly the speed-up you'll get 24/7 with Deactivator (but unlike manual deactivation, your gallery pages will remain fully functional).
Especially effective when using NextGEN v2.0.xx, Deactivator also deactivates NextGEN Legacy (v.1.9.xx), the NextCellent Gallery fork, and will even deactivate the NextGEN Gallery Pro or Plus add-ons simultaneously (if installed alongside NextGEN 2.0).