New Bug-Fix Releases for MPS Versions 2026.2 RC2, 2026.1.2, 2025.3.3, 2025.2.5, and 2025.1.5

JetBrains Blog Developers & Open Source 11/02/2026, 13:13 Score 8/10

Summary

We’ve released updates for multiple MPS versions that fix a critical security issue. MPS 2026.1.2 and 2026.2 RC2 additionally bring a substantial improvement to the Projectional Agent Toolkit plugin. For the latest information on the security issue and the steps we’ve taken to address it, please read our dedicated blog post – Compromised eMudhra Certificates: […]

Original Text

For the latest information on the security issue and the steps we’ve taken to address it, please read our dedicated blog post – Compromised eMudhra Certificates: Update Your JetBrains IDEs.

One important fix required on your end if you are on 2025.1.5 or 2025.2.5: Disable JCEF by turning off the ide.browser.jcef.enabled flag in the MPS Registry. Read detailed instructions in the Disable JCEF in your IDE section of the announcement.

As JBR and JCEF are affected by the security problem, this is likely to affect MPS-based RCP applications. If you build and distribute RCP applications, please read the above-mentioned post and perform all necessary actions to secure your RCP applications properly.

DOWNLOAD MPS 2026.1.2

MPS 2026.1.2 and 2026.2 RC2

The Projectional Agent Toolkit plugin receives all the improvements that are planned for MPS 2026.2, including:

Consolidated MCP tool API

Numerous performance improvements

Type system MCP tool

Intention actions and quick-fixes

Automatic skill database updates

Access to the content of MPS logs

Opening, closing, and creating MPS projects

Automatic correction of SModel expressions in parsed Java statements

And many more

Note: Remember to ask your agent to update the MPS skills in your project to reap the full benefits of these changes.

Download MPS 2026.1.2 here.