Filter for imported strings

We often talk about issues, but we forget to highlight the qualities of a
product.
I've been doing a lot of volunteer localization with Babelzilla, Transifex,
Crowdin and more. Pontoon is as good as the best ones.
We appreciate the hard work performed by its team.
I understood Francesco's explanation about imported strings. But with due
respect to other pt-BR localizers, we're all human beings, we all make
mistakes. Even already approved translations need review.
I started contributing to localizing Mozilla KB & products precisely
because there was so many wrong and outdated translations, and I know the
impact localization errors have on a product's image, specially Firefox
that I value so much.
So, I request again just a small change in Pontoon: add IMPORTED to the
author filter.
If possible, adding an option to filter only the author's approved strings
(instead of all strings that had their contribution) would be even better.

Thanks,
Marcelo