Incompatible Changes in IntelliJ Platform and Plugins API 2026.*

Please see Verifying Plugin Compatibility on how to use Plugin Verifier and IDE inspections to check such problems.

Early Access Program (EAP) releases of upcoming versions are available here.

2026.1

IntelliJ Platform 2026.1

AWT input event handlers no longer run under write-intent lock: Custom input handlers (KeyListener, MouseAdapter, etc.) no longer execute under the write-intent lock. If PSI or other write-intent-protected data needs to be accessed in these handlers, explicitly acquire a read action using ReadAction.nonBlocking().submit() or coroutine-based equivalents such as readAction {}.

PolySymbols

com.intellij.polySymbols.PolySymbol.getOrigin() method removed

The property was confusing and in many cases was not used. Its functionality is replaced by:

framework property - provide com.intellij.polySymbols.html.HtmlFrameworkSymbolsSupport.HtmlFrameworkIdProperty value through PolySymbol.Property mechanism

defaultIcon property - implement icon property and return true for PolySymbol.DocHideIconProperty through PolySymbol.Property mechanism

typeSupport property - provide com.intellij.polySymbols.utils.PolySymbolTypeSupport.TypeSupportProperty value through PolySymbol.Property mechanism

com.intellij.polySymbols.PolySymbolQualifiedKind class renamed to com.intellij.polySymbols.PolySymbolKind

additionally name property was renamed to kindName and qualifiedKind properties and parameters across the package were renamed to kind

The following classes no longer implement PsiModificationTracker (this requirement was confusing):

Implementing PsiModificationTracker was replaced by modificationTracker property for the following classes:

Java Plugin 2026.1

The Java plugin has been split into several modules with their own classloaders. This shouldn't affect plugins that use standard <depends>com.intellij.java</depends> dependency. If a plugin depends on specific Java plugin modules directly, the dependencies should be updated to reference the new module names.

20 April 2026