I don't know if all of them should be documented, but VarDumper added a ton of new features in Symfony 3.2:

• Add maxDepth & maxStringLength display options ([VarDumper] Add maxDepth & maxStringLength display options symfony#18948), will be covered byDocument new environment variables and display options #7217
• Get dump as string with$dumper->dump(..., true); ([VarDumper] Get dump as string with$dumper->dump(..., true); symfony#19755)
• Add LinkStub to create links in HTML dumps ([VarDumper] Add LinkStub to create links in HTML dumps symfony#19816)
• Add ClassStub for clickable & shorter PHP identifiers ([VarDumper] Add ClassStub for clickable & shorter PHP identifiers symfony#19826)
• Add flags to allow fine tuning dumps representation ([VarDumper] Add flags to allow fine tuning dumps representation symfony#17305), will be covered byDocument new environment variables and display options #7217
• Allow dumping subparts of cloned Data structures ([VarDumper] Allow dumping subparts of cloned Data structures symfony#19672)
• Optionally pass dumper into DumpExtension ([Bridge][Twig] Optionally pass dumper into DumpExtension symfony#18466)