How to make Promotion/Discount Codes NOT be case-sensitive?

Hello,



I’m currently running version 2.1.3 and I would like to make promotion/discount codes to be case-unsensitive. Right now I have to make several versions of a promotion/discount code for the people who enter it in all capitals, all lower case and other combinations.



Any help would be greatly appreciated…



I did find someone asking the same question and there was a code fix. When I made the recommended code change, it resulted in an error though.



Thanks in advance…



Eric