I recently downloaded a lockscreen theme which made the slider invisible, and it also removed the transparent rectangular box that the lockscreen clock sits in. I'm wondering if there is a tweak or something that can do the same thing.
Unfortunately it's an UI image that can't be replaced except by using a theme. You can make a theme with only that one image though. Download the image below, rename it UILCDBackground.png, go to the themes directory on the phone (/var/stash/Themes.????), create a new directory named anything, let's call it "yourtheme", create a directory called UIImages inside there and put the transparent image in the UIImages folder. Select "yourtheme" in Winterboard and you're done.
You can use it with another theme by adding the image to the themes UIImages folder or creating one if necessary.
The image is completely transparent. Right click between the dashes to save it.
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