tcb_main_frame_enqueue

See hook in action

See this hook used in plugins:

Select Pluginall-in-one-seo-pack.4.6.6all-in-one-seo-pack.4.6.8.1all-in-one-seo-pack.4.6.9.1all-in-one-seo-pack.4.7.0all-in-one-seo-pack.4.7.1.1all-in-one-seo-pack.4.7.3all-in-one-seo-pack.4.7.4.2