What is the first action or filter executed by wordpress?
Here is nicely described what and when is loading and why. I recommend also this awesome plugin Query Monitor that helped me also to fix performance issues. in short: muplugins_loaded registered_taxonomy registered_post_type plugins_loaded sanitize_comment_cookies setup_theme unload_textdomain load_textdomain after_setup_theme auth_cookie_malformed auth_cookie_valid set_current_user init widgets_init register_sidebar wp_register_sidebar_widget wp_loaded parse_request send_headers parse_tax_query parse_query pre_get_posts posts_selection wp template_redirect wp_default_scripts … Read more