includes/managers/class-fs-admin-menu-manager.php
function is_main_settings_page() {
			if ( $this->_menu_exists &&
			     ( fs_is_plugin_page( $this->_menu_slug ) || fs_is_plugin_page( $this->_module_unique_affix ) )
			) {
				/**
				 * Module has a settings menu and the context page is the main settings page, so assume it's in
				 * activation (doesn't really check if already opted-in/skipped or not).
				 *
				 * @since 1.2.2
				 */
				return true;
			}

			global $pagenow;
			if ( ( WP_FS__MODULE_TYPE_THEME === $this->_module_type ) && Freemius::is_themes_page() ) {
				/**
				 * In activation only when show_optin query string param is given.
				 *
				 * @since 1.2.2
				 */
				return fs_request_get_bool( $this->_module_unique_affix . '_show_optin' );
			}

			return false;
		}
function is_main_settings_page() {
			if ( $this->_menu_exists &&
			     ( fs_is_plugin_page( $this->_menu_slug ) || fs_is_plugin_page( $this->_module_unique_affix ) )
			) {
				/**
				 * Module has a settings menu and the context page is the main settings page, so assume it's in
				 * activation (doesn't really check if already opted-in/skipped or not).
				 *
				 * @since 1.2.2
				 */
				return true;
			}

			global $pagenow;
			if ( ( WP_FS__MODULE_TYPE_THEME === $this->_module_type ) && Freemius::is_themes_page() ) {
				/**
				 * In activation only when show_optin query string param is given.
				 *
				 * @since 1.2.2
				 */
				return fs_request_get_bool( $this->_module_unique_affix . '_show_optin' );
			}

			return false;
		}
function is_main_settings_page ( ) { if ( $ this -> _menu_exists && ( fs_is_plugin_page ( $ this -> _menu_slug ) || fs_is_plugin_page ( $ this -> _module_unique_affix ) ) ) { /**
				 * Module has a settings menu and the context page is the main settings page, so assume it's in
				 * activation (doesn't really check if already opted-in/skipped or not).
				 *
				 * @since 1.2.2
				 */ return true ; } global $ pagenow ; if ( ( WP_FS__MODULE_TYPE_THEME === $ this -> _module_type ) && Freemius :: is_themes_page ( ) ) { /**
				 * In activation only when show_optin query string param is given.
				 *
				 * @since 1.2.2
				 */ return fs_request_get_bool ( $ this -> _module_unique_affix . '_show_optin' ) ; } return false ; }
Is user on plugin's admin activation page.

@author Vova Feldman (@svovaf)
@since  1.0.8

@return bool
Is user on plugin s admin activation page .