The last picture you had , looked a lot like Suzi! She does the same thing. Perring hrough the blinds, then going nutso when someone walks on the sidewalk near our APT. God forbid they come up the stairs. Suai has a huge bark, i mean a really loud big bad A** bark. The poor post lady does not have a chance. She leveave the packaged at the doorway, while Suzi barks her head off all the way to her car.
She really hates it when a man knocks on the door. The man thought i had a pit bull

I picked Suzi up and this time it helped her calm down, sometimes it does not help and she wiggles her way out of my arms.
SHe definately is our wathcdog. By the way I have seen people coming up our door, and Suzi barking barking crazy, they atually turn around and leave, not even knocking .