OK- Strange Passerine.
I will go through a complete breakdown of characteristics.
Location: Eastern Nebraska, United States
Color: Brown of light to medium darkness. Front maybe a bit paler. White to light brown eyestripe.
Shape: Like a slightly longer, stockier warbler. Not much stockier.
Size: 5-7 Inches. (Sorry, not so helpful)
Habitat: A marshy area in a park with trees and lots of cover
Call/Song: A mix of chattering and warbling, not a trill. Not OCWA.
Pattern: Dull brown on most of body. No streaks on breast or anywhere else on body or wings.
Tail: Brown, no bars, not sticking up like a wren
I have absolutely no idea whatsoever, unless this is something really rare like an Old World Warbler.
If you have any ideas @johnnybirder @john8 @psweet it would be really helpful. Sorry to bug you over a mystery bird.
Thanks!