Hi Kerry.
First of all try to check the checkbox in "Site Administration -> Appearance -> Html editor". If its switched off, try to turn it on. But if its turned on, try check your config.php for errors.
Or simply copy original config-dist.php to config.php and fill it with your database connection settings and site directories settings, you do not need to set other options.
The absence of html editor is not the browser issue. In my case there was unnecessary symbols in config.php that makes editor unseen.