For major new features in 3.2, please see the Beta announcement https://github.com/icsharpcode/ILSpy/releases/tag/v3.2-beta. Here we list only the changes from Beta -> RC.

Contributions

Improved control-flow decompilation of conditional statements (special thanks to @Chicken-Bones #1176 )
Search engine partial name match (special thanks to @TheOneAmir #1119 )

Improvements & Bugfixes

Improved stability of ILSpy.AddIn
Avoid ambiguities when referring to Attribute types in attribute context
Improved decompilation of Windows Forms assemblies
Improved code generation when using generic methods (emit fewer casts, if possible)
Support for extension 'Add' methods in collection initializers (forgotten C# 6.0 feature)
Improved decompilation of collection initializers
Use overload resolution to ensure we call the correct indexer accessor methods
Streamlined decompilation of enum value declarations
... as well as other minor fixes