Local Community

Why does a plugin fail to activate?

I get a fatal error trying to add a plugin to filter woocommerce products. Fatal error Uncaught Error: Undefined constant “SECURE_AUTH_KEY” in " Local Sites/stagefarbest/app/public/wp-content/plugins/premmerce-woocommerce-product-filter/freemius/includes/class-freemius.php on line 4061"

Do I need working SSL? I had trouble getting the SSL trusted.

Any ideas?