User blog comment:Otakon7/Otakon7's Buddyfight Simulator/@comment-10483040-20160310040818/@comment-2234004-20160310121811

Well, I simply meant a different browser so I can rule out caching.

Chances are, with the new sim being in a subdirectory is causing issues.

P.S. when you can, try to "Load" a deck and see if the deck is there, even with the error during saving.