Hey You don’t need any key untill the plugin updates. You can use plugin with COSMOS theme. If you want to update yourself you need to purchase licence key for this plugin. But We’re tracking our themes bundled premium plugins and We are updating all plugins our side. You’ve already updated latest version of this plugin.

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ThemeofWP.com Team

Please install this modified version and don’t update it. https://themeofwp.com/plugins/base-shortcode-for-bootstrap.zip

Regards
Themeofwp.com Team.