Extensions listed in `devcontainer.json` not installed into Remote Extension Host

[mrmachine]

Describe the Bug

In my .vscode/extensions.json and .devcontainer/devcontainer.json files I list the same extensions:

	"extensions": [
		"anysphere.cursorpyright",
		"anysphere.remote-containers",
		"batisteo.vscode-django",
		"csharpier.csharpier-vscode",
		"davidanson.vscode-markdownlint",
		"eamodio.gitlens",
		"editorconfig.editorconfig",
		"eriklynd.json-tools",
		"esbenp.prettier-vscode",
		"humao.rest-client",
		"idleberg.innosetup",
		"mechatroner.rainbow-csv",
		"ms-python.black-formatter",
		"ms-python.python",
		// "ms-python.vscode-pylance",
		"ms-vsliveshare.vsliveshare",  // @1.0.5905",  // https://forum.cursor.com/t/sharing-cursor-ide-project/13152/5
		"redhat.vscode-yaml",
		"yzane.markdown-pdf",
		"yzhang.markdown-all-in-one",
	],

But after doing Dev Containers: Rebuild Container, Cursor reports that many extensions are:

… disabled in this workspace because it is defined to run in the Remote Extension Host. Please install the extension in ‘Container … (877867cb37e9)’ to enable. Learn More

And show a blue Install in Container ... button.

I can click each one to manually install them, but there are a LOT of them. And they are NOT installed again every time I do Dev Containers: Rebuild Container.

Steps to Reproduce

Add the following extensions to .vscode/extensions.json and .devcontainer/devcontainer.json:

dbaeumer.vscode-eslint
bradlc.vscode-tailwindcss
charliermarsh.ruff
mhutchie.git-graph
github.vscode-github-actions

Do Dev Containers: Rebuild Container.

Observe that those extensions are NOT installed in the extensions list when you filter by @disabled or @installed @sort:installs.

Expected Behavior

Extensions listed in .devcontainer/devcontainer.json that prefer to run in the Remote Extensions Host should be installed there automatically after container rebuild.

Screenshots / Screen Recordings

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Version: 1.2.4
VSCode Version: 1.99.3
Commit: a8e95743c5268be73767c46944a71f4465d05c90
Date: 2025-07-10T16:53:59.659Z
Electron: 34.5.1
Chromium: 132.0.6834.210
Node.js: 20.19.0
V8: 13.2.152.41-electron.0
OS: Darwin arm64 24.5.0

Does this stop you from using Cursor

No - Cursor works, but with this issue

[ravirahman]

Hi @mrmachine, extensions listed inside the .vscode/extensions.json are “recommended” and won’t auto-install.

However, extensions listed inside the .devcontainer/devcontainer.json should auto-install. Can you confirm they are in the correct section (vscode.customizations.extensions)? E.g.

{
    "name": "Dev container"
    // ...
	"customizations": {
		"vscode": {
			"extensions": [
				"anysphere.cursorpyright",
				"anysphere.remote-containers",
				"batisteo.vscode-django",
				"csharpier.csharpier-vscode",
				"davidanson.vscode-markdownlint",
				"eamodio.gitlens",
				"editorconfig.editorconfig",
				// ...
			]
		}
	},
}

[mrmachine]

You are correct. My bad. My recommended extensions list was not even complete. I did not notice that many of the extensions that were not automatically installed in the container were not even listed in devcontainer.json OR extensions.json, but appear to have been installed manually.