I think that sometimes there are multiple attempts to update happening at
the same time, with the result that one of them gets an error, but if you
check the app moments later, the definition is there. I assume there must
be some kind of mechanism to take care of this--perhaps if there's no user
action, it would have gone in 24 hours later at whatever time AU updates are
set to install, or on next login--not sure.
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