Finder- getting rid of divider bar in every new window I have had new finder windows open with a weird divider bag (marked in red in picture below) on the right side for quite some time now. I have dealt with it by dragging the bar to the right until it disappears but am starting to get annoyed having to do this every single time.


I tried several ways to reset the finder size but they have not helped getting rid of the weird bar thing. 

Please let me know if you have any idea what could fix this. I am running macOS Mojave 10.14.4.
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