If you have Windows this should work....
First of all, you need to be able to see the file extensions. In this case, they should be ".jbr" If you can't see them, you're going to have make it so you can see them, it's in the options of your files somewhere....
After you can see the extensions, all you have to do is rename the file, and change ".jbr" to ".abr" I would test one first, because I'm not sure if this would work on all operating systems.
I hope it works!
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