Description
When the Extension Gallery latest-version resource returns a successful response whose version metadata omits the files array, VS Code assumes the array exists while resolving assets. This throws Cannot read properties of undefined (reading 'filter').
The error is caught and VS Code falls back to the Gallery query API, so extension update discovery can still succeed, but each check produces misleading errors such as:
Error while getting the engine for the version <version>. Cannot read properties of undefined (reading 'filter')
Error while getting the latest version for the extension <extension-id>. Cannot read properties of undefined (reading 'filter')
The response shape was observed from the Microsoft-managed Marketplace feed for these extensions:
ms-vscode.vscode-chat-customizations-evaluations — 1.1.2026072818ms-vscode.ts-customized-language-service — 1.1.2026072402redhat.vscode-yaml — 1.25.2026080108
The same three failures repeated during a subsequent update check. Feed versions may have advanced since the observation. The public Marketplace latest-version endpoint currently includes files, so reproducing outside an environment with the Microsoft-managed/private Gallery may not be possible.
Reproduction
- Run the latest VS Code Insiders in an environment configured with a managed/private Extension Gallery whose latest-version resource can omit
versions[].files.
- Install or enable one of the affected extensions listed above. All three produced the error in the observed logs.
- Run Extensions: Check for Extension Updates from the Command Palette.
- Run Developer: Open Logs Folder.
- Open the newest session's
window1/renderer.log and search for reading 'filter' or Error while getting the engine.
The same entries may also be visible in the Developer Tools console.
Expected
VS Code should treat a latest-version response without asset-file metadata as incomplete and use the existing query API fallback without logging an exception.
Actual
Asset lookup throws before the existing fallback runs, causing error-level log entries even though the fallback can recover.
Description
When the Extension Gallery latest-version resource returns a successful response whose version metadata omits the
filesarray, VS Code assumes the array exists while resolving assets. This throwsCannot read properties of undefined (reading 'filter').The error is caught and VS Code falls back to the Gallery query API, so extension update discovery can still succeed, but each check produces misleading errors such as:
The response shape was observed from the Microsoft-managed Marketplace feed for these extensions:
ms-vscode.vscode-chat-customizations-evaluations—1.1.2026072818ms-vscode.ts-customized-language-service—1.1.2026072402redhat.vscode-yaml—1.25.2026080108The same three failures repeated during a subsequent update check. Feed versions may have advanced since the observation. The public Marketplace latest-version endpoint currently includes
files, so reproducing outside an environment with the Microsoft-managed/private Gallery may not be possible.Reproduction
versions[].files.window1/renderer.logand search forreading 'filter'orError while getting the engine.The same entries may also be visible in the Developer Tools console.
Expected
VS Code should treat a latest-version response without asset-file metadata as incomplete and use the existing query API fallback without logging an exception.
Actual
Asset lookup throws before the existing fallback runs, causing error-level log entries even though the fallback can recover.