I was messing with the Lockbackground.html file over the weekend, and kinda figure out a work around for the time being, before a fix is released from Cydia.
There are 2 steps to this process.
1 - I opened Lockbackground.html with wordpad or notepad, search for the text:
background-color: #000;
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then I changed the color (#000) to none.
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2 - SSH or use ifile and goto your LockHTML/Winterboard theme(XXXX) directory, rename or delete the file LockBackground.jpg (or whatever your theme wallpaper is called)
LockHTML - /var/mobile/Library/LockHTML/XXXX/LockBackground.jpg
Winterboard - /var/Library/Themes/XXXX/LockBackground.jpg
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The result is NOT perfect, you HTML widget will overlap the notification, but at least you can see it without unlock your phone
before:
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after:
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