A client's MSM powered EE 2.6.1 site including Matrix 2.5.5 has just gone live and new entries with empty Matrix fields are ending up with 'czowOiIiOw==' in them – this I understand is a PHP base 64 encoded empty string.
This of course causes template logic that hinges on empty fields to break!
Any suggestions for a fix? I can go into the database and clear 'czowOiIiOw==' but I'd like to do better than that ;)