IntelliJ IDEA 2026.2 Help

Code highlighting

You can configure code highlighting options for Scala code in settings. Press Ctrl+Alt+S to open settings and then select Languages & Frameworks | Scala | Editor.

IntelliJ IDEA with Scala Plugin offers two modes of error highlighting: Built-in and Compiler.

Scala Highlighting

Built-in highlighting

Built-in highlighting is the default highlighting mode. It offers more features and faster feedback and is overall more lightweight.

Scala Built-in Highlighting

When Built-in highlighting is selected, the Incremental highlighting option becomes available. Enable this option to limit syntax highlighting to the visible area of the editor. This may improve performance and reduce CPU, memory, and battery usage, especially when editing large or complex files.

Compiler-based highlighting

Compiler highlighting provides more accurate error and warning reporting because it uses the Scala compiler. However, it is slower, consumes more resources, and does not support some IntelliJ IDEA features, such as inspections, quick-fixes, and type diffs. Unless you encounter a significant number of false positives, Built-in highlighting is recommended.

Scala Compiler-based Highlighting

When the Compiler highlighting is selected, the following options become available:

  • Disable built-in inspections: some inspections provided by the Scala plugin overlap with compiler diagnostics or add only a small amount of additional information. Disabling these inspections can help improve editor performance.

  • Use types reported by the Scala compiler: use type information provided by the compiler for type inference in macros and in transparent inline methods.

Other highlighting options

You can find more highlighting options in the Advanced section on the page Languages & Frameworks | Scala | Editor:

Title

Example

Highlight implicit conversions

Highlight: Implicit conversion

Show hints on type mismatch

Highlight: Type mismatch

Show hints if no implicit arguments found

Highlight: No implicit argument found

Show hints if ambiguous implicit arguments found

Highlight: Ambiguous implicits

Highlight arguments to by-name parameters

Highlight: By-name parameters

Custom aliases are Exports/Definitions

Highlight: Exports/Definitions

Collection type highlighting

Highlight: Standard collections
16 June 2026