project setting "Store information about method parameters" cannot be changed for individual projects in a multi-root workspace

[chagong]

Environment:

VS Code Version: 1.107.1
Extension Version: 0.31.0
JDK Type & Version: RedHat 17.0.18
OS Type & Version: Windows 26100.8246
Step to Reproduce:

Load a multi-root workspace with multiple Java projects.
Open Project Settings by going to the JAVA PROJECTS pane, clicking the ellipsis/More Actions..., and choosing Configure Java Runtime.
Change the Project to the second project.
Choose the Compiler section.
Toggle "Store information about method parameters" to on.
Click Apply Settings.
Expected Behavior:
The selected project should have been built with the -parameters flag.

Actual Behavior:
The -parameters flag was not used.

Related Issues:
I can no longer toggle this switch for an individual project. The toggle remains set or unset for all projects.
This is a new problem since installing this version of the extension. It worked in the previous version.

[issuelens]

Investigation result

This is a high-confidence duplicate of microsoft/vscode-java-pack#1650: the title, VS Code 1.107.1 / extension 0.31.0 / Red Hat JDK 17 / Windows environment, multi-root reproduction sequence, expected -parameters result, and actual symptom all match exactly.

Affected area: the Java extension's Project Settings webview, specifically the project selector and compiler configuration controls.

Probable root cause: the React 19 / @vscode-elements/elements migration shipped in 0.31.0 changed these controls to vscode-single-select. Its options render in shadow DOM and emit the native change event on the host, so the previous React onClick handlers on slotted options never ran. Consequently activeProjectIndex remained 0, and applying the method-parameters toggle always targeted the first project rather than the selected project.

Supporting evidence and fix: upstream PR #1655, merged as commit 3407fd6, fixes #1650 by listening for native change events in ProjectSelector and CompilerConfigurationView, then syncing the selected values from Redux. Its verification confirms that org.eclipse.jdt.core.compiler.codegen.methodParameters=generate is written only to the selected project's JDT preferences.

Reproduction: use a multi-root Java workspace, select the second project in Java: Open Project Settings, enable Store information about method parameters, and apply. On the affected build, the first project is still targeted and the selected project does not receive -parameters.

The upstream fix is the appropriate remediation; this report does not indicate a separate IssueLens defect.