An internal error occurred during: "Loading descriptor for FOO_PROJECT_NAME.".

[olirumiffol]

Steps to reproduce

From a fresh installation of the 2024-12 version and clean workspace from previous installation:
(PS.: I tried both, clean and reused workspace)

First, upgrate to version 2025-03

I tried:

• Importing my project in a new workspace, just after updating
• Opening my maven project, imported in the previous version

I expected:

• Project loading without error

But got: Error message (every ~1 second in a loop) stating "An internal error occurred during: "Loading descriptor for MY_PROJECT_NAME."."

Expanding the details displays:

An internal error occurred during: "Loading descriptor for FOO_PROJECT_NAME.".
class org.eclipse.jst.j2ee.webapplication.internal.impl.WebAppImpl cannot be cast to class org.eclipse.jst.javaee.web.WebApp (org.eclipse.jst.j2ee.webapplication.internal.impl.WebAppImpl and org.eclipse.jst.javaee.web.WebApp are in unnamed module of loader org.eclipse.osgi.internal.loader.EquinoxClassLoader @252749a9)

As pointed by the user @merk at eclipse-platform/.github issues page, apparently the problem is here due to the type cast in this method.

Link to Merk's comment.

Here is some relevant log output

From <workspace>/.metadata/.log

Uploaded my log with pc user and project name supressed:

.log

Tested under this environment:

• OS & version: Windows 11 24H2, my JAVA_HOME is set to LibericaJDK 8.0.422-b07

• Eclipse IDE/Platform version (as shown in Help > About):
  Version: 2025-03 (4.35.0)
  Build id: 20250306-0812

• Installation Details:

installation_details.txt

[olirumiffol]

By the way, this bug doesn't happen in a fresh installation of Eclipse IDE 2025-03. It's only when upgrading from 2024-12 to 2025-03.