TypeScript 7 VS Code extension: let extensions that serve their language through content mappers opt out of the tsserver-plugin warning

[leonidaz]

🔎 Search Terms

• TypeScript server plugins from the will not be loaded because TypeScript 7 is enabled globally
• warnAboutTsServerPlugins typescriptServerPlugins content mapper

🕗 Version & Regression Information

• The TypeScript 7 VS Code extension built from packages/vscode-typescript at f29aeb9 (main, 2026-09-16), VS Code 1.138.0, macOS 26.6 x64
• The warning and its exemption list are unchanged since the published TypeScriptTeam.native-preview 0.20260708.2

⏯ Playground Link

n/a (VS Code extension behaviour)

💻 Code

warnAboutTsServerPlugins in packages/vscode-typescript/src/extension.ts warns once per session, when js/ts.experimental.useTsgo is set at user level, for every installed extension whose manifest contributes typescriptServerPlugins:

TypeScript server plugins from the "TSRX.tsrx-vscode-plugin" extension will not be loaded because TypeScript 7 is enabled globally.

The only exemption is the hardcoded suppressedPluginExtensionIds set (github.copilot, github.copilot-chat).

An extension for a content-mapped language needs both mechanisms: a typescriptServerPlugins contribution so that VS Code's built-in TypeScript extension (TypeScript 5.9/6, tsserver) can serve its files, and a content mapper (declared in the project's tsconfig.json under contentMappers) so that TypeScript 7 can. When TypeScript 7 is enabled, the plugin is intentionally not needed: the mapper takes over. The warning is then accurate but misleading, since the extension's language works fine.

🙁 Actual behavior

Every user of such an extension who enables TypeScript 7 globally sees a warning suggesting the extension is broken under TypeScript 7, with "Disable Native Preview in Workspace" offered as a remedy, although nothing is lost.

🙂 Expected behavior

A way for an extension to declare that its language is served through content mappers on TypeScript 7, for example a per-plugin flag on the contribution ("typescriptServerPlugins": [{ "name": "...", "contentMappers": true }] or similar), which the warning would then skip, as it skips the hardcoded ids today.

Additional information about the issue

Found while wiring the TSRX VS Code extension (tsrx-org/tsrx#135); its README currently tells users to dismiss the warning with "Don't Show Again".