This app was mentioned in 3 comments, with an average of 1.33 upvotes
Unless things have changed, IIRC you need to be rooted.
From there, you can just use this app from the Play store to turn it on/off and not break screenshot functionality.
I've updated the app to provide a second method of disabling Clip Tray (I had reports of the original method causing problems with taking screenshots) and I've got it published on the Google Play store now.
If you're rooted, there is this. Use it on mine, no issues.