Currently default tinyMCE buttons are used :

• they simply call the browser command that do not work on firefox.
• of course they currently do not intercep the shortcuts
• the word clean button is not used (tinyMCE version not cool enought)
• the text only button is not used (tinyMCE version not cool enought)

The paste2 plugin should be checked to see if it do resolves the word clean problem