Makes all keywords case insensitive (creates all keywords and calls all keywords lowercase.) Only works if you are using Base 36. Fixes disappearing capital letters.
Move the case-insensitive folder into the /users/plugins folder. Then, activate the plugin in the admin interface. That's all there is to it.
User must have YOURLS 1.5.1+ installed.
Works with YOURLS QR Code Plugin to generate smaller QR codes!
Borrowed code from Ozh's Force Lowercase plugin