Downloaded Squeak3.11-9371-alpha.zip, and see the notes mention in What's New?:
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Installer update
Installer has been updated to the latest version which includes support for automatically parsing mantis bug reports and operating on them, for example:
	Installer mantis bugsAll select:[:bug| bug status = 'feedback'].
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Checking in Monticello Browser in the image, I see Installer-Core-cmm.336.

Checking in the Installer Repository:
<http://www.squeaksource.com/Installer.html>

I see only Installer-Core-mtf.335.mcz.
Matthew Fulmer recently went to quite a bit of work in order to bring the Installer repository up to date with things that have been changed elsewhere ie trunk, and not updated in the Installer repo. It seems that trunk Installer-Core has yet again diverged.

What's New also mentions:
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Modularity
The following packages have been made reloadable: ReleaseBuilder, ScriptLoader, 311Deprecated, 39Deprecated, Universes, SMLoader, SMBase, Installer-Core, VersionNumberTests, VersionNumber, Services-Base, PreferenceBrowser, Nebraska, CollectionsTests, GraphicsTests, KernelTests, MorphicTests, MultilingualTests, NetworkTests, ToolsTests, TraitsTests, XML-Parser, Traits, SystemChangeNotification-Tests, FlexibleVocabularies, EToys, Protocols, Tests, SUnitGUI.
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If these unloadable/reloadable packages are ever to be externally managed, it seems to me that there needs to be some mechanism put into place which blesses the appropriate master repository for each package so that it is kept as the most current.

Ken G. Brown