Turning off <pre> formatting with richtext toolbar doesn't reset style properly

[johnbotris]

• type some text
• select it and press <> button in the formatting toolbar
• press the <> button again
• see that the text isn't back in the default style

example:

Test notes

Test on Safari, Chrome, Firefox

• [ ] Compose a new mail in the editor
• [ ] Type the same text on two lines
• [ ] Highlight one line, turn preformatted text on (the <> button), and then turn it off.
  • [ ] Verify the lines look the same
• [ ] previous test works with bolded and italicized text