function back() {
    if (this.desiredCapabilities.browserName === 'safari') {
        /*!
         * helper for safaridriver which doesn't not support forward
         * Reason: "Yikes! Safari history navigation does not work. We can go forward or back,
         * but once we do, we can no longer communicate with the page"
         */
        return this.execute('history.go(-1)');
    }

    return this.requestHandler.create({
        path: '/session/:sessionId/back',
        method: 'POST'
    });
}
Navigate backwards in the browser history, if possible.

@see https://w3c.github.io/webdriver/webdriver-spec.html#back
@type protocol