Last modified: 2011-09-19 04:54:17 UTC
See dependencies. Behavior can be seen on 1.18 and trunk with Gadgets installed. See translatewiki.net for example where gadget "No-op" is enabled by default but can't be disabled by the user (when one attempts to and save, it'll still be ticked again). See dependency bugs for more technical details.
Just tested on twn, works for me now.