"I looked out the window, and I saw you."

Translation: J'ai regardé par la fenêtre et je t'ai vu.

[Sciuro4]

Can't it also be "je t'ai vue" when 'tu' refers to a woman, or does the direct object only change to match the preceeding pronoun if it is third person?

[Jojo553168]

It could be je t'ai vue. It should be accepted.

[Sitesurf]

"Je t'ai vue" is accepted, as well as "Je vous ai vu/vue/vus/vues", since "vous" is possible and can be singular or plural, masculine or feminine.

[Vic.BR]

... travers la fenetre ???

[GraemeSarg]

I'm pretty sure that involves physically passing through the window.

[Aidan424456]

One doesn't "look out the window" unless one is in America or speaking American - which I'm not. And Duo knows it. They need to recognise American and English as distinct languages.

[Sitesurf]

They do and they picked American English everywhere on Duolingo.