Indented text in private messages produces unwrapped code blocks

[eatyourgreens]

Expected behavior

Inbox messages should wrap to fit the width of their container.

Current behavior

Please include any error messages from the browser console and/or screenshots

If you accidentally create a code block, by indenting a paragraph, the resulting text is displayed as one long line that flows off the edge of the screen.

Steps to replicate

Write a PM to yourself, including at least one paragraph that is indented by four spaces.

Additional information

See Message lines not wrapping on Zooniverse Talk.

[eatyourgreens]

Fixed by #7106.

[eatyourgreens]

This is the same bug as #1599, but for inbox messages rather than Talk comments.