In moving from 2.10.x to 2.11.x, the testimonial HTML was changed to use `blockquote` than `q`. The reason being is that `q` is meant for inline quotations. However, that’s not what we were using it for. Hence, `blockquote`.
If you want `q` tags back, just enable “Use `q` tags?” on the Compatibility & Reset tab of Testimonials > Settings.
Lastly, using `blockquote` is HTML 5 valid.