2.4.2.1 release notes

2.4.2.1

  • Removed support for JetBrains 2025.2 IDEs. Please make sure that you're using 2025.3+ (ideally the latest-and-greatest which is currently 2026.2.2) for continued IC plugin updates.
  • Issue 3019 - Fixed a problem with commas in ApexDoc @see description text being interpreted incorrectly as a comma-delimited list of targets.
  • Issue 3020 - Fixed a potential deadlock calculating the server time offset during the first Deploy Modified Metadata action against a specific connection after starting the IDE.
  • Added support for per-test code coverage in aer. This is accessed using the IDE's standard per-test coverage feature. Note that you must be using aer 1.4+, and you must explicitly enable the feature in Illuminated Cloud | Configure Application | Apex | Apex Execution Runtime (aer) | Enable coverage by test.
  • Integrated broad improvements in the OST's Apex system types based on the upcoming Apex Symbol API. In this version, IC does not yet use that API - it will be offered as an option when Winter '27 is GA - but this provides many of the fidelity benefits of that API that have not been available in the Tooling API's completions?type=apex REST resource. To see the effects of this change, you must regenerate your OST.
  • Fixed an issue that could result in a newly-generated OST being perceived as invalid by the IDE because of concurrent read access to update .illuminatedCloud/lwc/types while still writing the OST archive.
  • Fixed an issue showing SOQL Query tool window results when conversion of scientific values is enabled.