You cannot format plain text so there is no need for a format toolbar. The format toolbar is only available when using HTML.

I want to turn formatting back on. The "plain text" button was in the Format Menu. I can't figure out how to turn "plain text" off. Thanks.

Check in the Account Settings, under Composition & Addressing. There is a checkbox there labelled "Compose messages in HTML format". This sets the default composing mode for that account. If you tick this checkbox, it will start new messages using HTML formatting.

You don't say you have done anything to change this setting, but the formatting options won't automatically appear until this checkbox is ticked.

The checkbox sets the default composition mode for its account. You can temporarily switch to the alternative mode by holding down the shift button when clicking on Write.

Over and above all this, even if HTM formatting is enabled, it is also possible to hide the Formatting bar. So, if you have lost an entire toolbar, look at View|Toolbars in the Composition window, and select the Formatting Toolbar option.

THANK YOU!!