### Preflight Checklist - [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) and this hasn't been reported yet - [x] This is a single bug report (please file separate reports for different bugs) - [x] I am using the latest version of Claude Code ### What's Wrong? All the extensions are displayed under the 'Explorer'. ### What Should Happen? extensions should display in siderbar. ### Error Messages/Logs ```shel

[BUG] All the extensions are displayed under the 'Explorer' in Antigravity.

Status Closed — not planned

Maintainer reply None cached

Activity 13 comments · opened Dec 16, 2025 · closed Feb 27, 2026

Preflight Checklist

[x] I have searched existing issues and this hasn't been reported yet
[x] This is a single bug report (please file separate reports for different bugs)
[x] I am using the latest version of Claude Code

What's Wrong?

All the extensions are displayed under the 'Explorer'.

What Should Happen?

extensions should display in siderbar.

Error Messages/Logs

Anthropic.claude-code: Error: Extension 'Anthropic.claude-code' CANNOT use API proposal: contribSecondarySidebar.
Its package.json#enabledApiProposals-property declares: [] but NOT contribSecondarySidebar.
The missing proposal MUST be added and you must start in extension development mode or use the following command line switch: --enable-proposed-api Anthropic.claude-code
at _Te (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:3310:19242)
at vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:3621:72499
at Array.forEach (<anonymous>)
at rvi.i (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:3621:72298)
at WVa.a (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:3621:71835)
at WVa.d (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:3307:53993)
at WVa.acceptUsers (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:3307:53926)
at ins.Lb (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:6838:5711)
at dns.Ib (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:6838:4741)
at dns.mb (vscode-file://vscode-app/Applications/Antigravity.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:6837:19934)
error @ workbench.desktop.main.js:2797
workbench.desktop.main.js:2797 WARN [Anthropic.claude-code]: View container 'claude-sidebar-secondary' does not exist. All views registered to it will be added to 'Explorer'.
warn @ workbench.desktop.main.js:2797
workbench.desktop.main.js:2797 WARN [apollographql.vscode-apollo]: View container 'client-devtools' does not exist. All views registered to it will be added to 'Explorer'.
warn @ workbench.desktop.main.js:2797
workbench.desktop.main.js:2797 WARN [Dart-Code.dart-code]: View container 'flutter' does not exist. All views registered to it will be added to 'Explorer'.
warn @ workbench.desktop.main.js:2797
workbench.desktop.main.js:2797 WARN [Dart-Code.dart-code]: View container 'flutterPropertyEditorContainer' does not exist. All views registered to it will be added to 'Explorer'.
warn @ workbench.desktop.main.js:2797
workbench.desktop.main.js:2797 WARN [Dart-Code.dart-code]: View container 'sidebarDevToolsContainer' does not exist. All views registered to it will be added to 'Explorer'.
warn @ workbench.desktop.main.js:2797
workbench.desktop.main.js:2797 WARN [Dart-Code.dart-code]: View container 'sidebarDevToolsInspectorContainer' does not exist. All views registered to it will be added to 'Explorer'.

Steps to Reproduce

1, install 2.0.70
2, open a new project with Antigravity

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.0.62

Claude Code Version

2.0.70

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_

View original on GitHub ↗

13 Comments

chenwei791129 · 8 months ago

I also meet this issue

OS: macOS
antigravity version: 1.104.0
extensions version: 2.0.72

lyl-94 · 8 months ago

Same issue, my codex icon in Activity Bar is disappeared.

cristiantoaderdotcom · 8 months ago

Same issue in Cursor

isCopyman · 8 months ago

Secondary Sidebar not supported in this version of VSCode. Please update your VSCode to use. Opening in Activity Bar instead.

ngvoicu · 8 months ago

Same issue, opening in Explorer for 2.0.75 and antigravity 1.12.3

andybrandt · 7 months ago

Same issue in Cursor (2.2.44) with 2.0.75.

ngvoicu · 7 months ago

today an update came, still no connection to the antigravity ide and breaks the extensions

khalid-faiz · 7 months ago

There is a small fix, customize layout -> secondary activity bar, drag-n-drop claude code from the panel to the secondary activity bar

ngvoicu · 7 months ago

xinatcg · 7 months ago

same issue. antigravity
Antigravity Version: 1.14.2
VSCode OSS Version: 1.104.0
claude code plugin: Version 2.1.7

the codex can be open by command, but the icon is missing.
the cline totally cannnot display

can disable/enable codex/cline and side bar icon show again. but after restart or new workspace still same.

try add cline and show in the main side bar and drag to second side bar, works. restart still keep

maybe a temparay solution:

after install the claude code. try to enable codex/cline by add some context, then the view will show in main side bar
drag it to second the bar: codex icon missing but work. cline icon show and work.

btxe · 7 months ago

Claude Code for VS Code Extension - bugs ##

I simply disabled the 'Claude Code for VS Code' Extension in Antigravity,
and re-start Antigravity IDE, every icon suddenly get back in the Activity Items icon area (no more list in explorer)
I enabled 'Claude Code for VS Code' Extension, re-start --> Icon has be gone again.
-_____- ; what the ...

Analysis ##

'Claude Code for VS Code Extension' is designed to run on the latest VS Code. (If you check the file in the extension's installation directory, you'll find a 'secondary sidebar' entry in the package.json file.)

VS Code latest version 1.108 vs. Antigravity (fork of VS Code 1.104) --> Antigravity currently doesn't support the Secondary Sidebar feature (old version).

However, during the Claude Code Extension installation process, there's no clear indication of incompatibility or errors with VS Code OSS versions lower than a specific one.

Solution ##

Browse the Claude Code Extension installation folder and delete the secondary sidebar definition in package.json. ----> No error occurs --> The problem disappears completely. --> If you add an exception handling function within the 'Claude Code for VS Code Extension' to check if the current IDE version (VSCode OSS Version) is an older version that supports secondary sidebar, the error will be resolved. (As a result, errors with cursor and antigravity will disappear.)

Claude Code for VS Code Extension v2.1.7

a. Delete 'secondary sidebar' related section in
b. re-start antigravity
c. everything is fine.
d. But a few days later, If the CC extension is updated without this fix, this error will occur again.

Caution ##

If there is another extension that similarly includes secondary sidebar related content in its package.json --> When that extension will be activated after installation --> So the same error is expected to occur in Antigravity, cursor, etc.

github-actions[bot] · 6 months ago

Closing for now — inactive for too long. Please open a new issue if this is still relevant.

github-actions[bot] · 5 months ago

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.