Creates a separate Claude Desktop instance with support for Web Extensions
Go
209
136 commits
updated Oct 10, 2026
A custom installer for Claude Desktop that includes built-in extensions (and the ability to install your own).
Note: The extensions in question are Web extensions! Not to be confused with Local MCPs, which the client also calls Extensions and come in the dxt format.
Disclaimer: This is an unofficial, third-party modification of Claude Desktop that enables extension support. By using this installer, you acknowledge that:
You can run several copies of the client side by side, each with its own login, settings and sessions. Useful if you want multiple windows open, or if you have multiple accounts.
Turn on Manage multiple instances on the setup screen (shown on first launch, or with --show-setup). After its usual checks, the launcher then shows a list of your instances instead of launching straight away:
The instance you've been using all along is Main. Its data folder was called Claude-modified before; the launcher renames it to Claude-Main the first time it runs while that instance is closed. Instances you already had are added to the list automatically.
The launcher's own menu entry (plain "Claude Desktop (Extended)") opens the list. You can also skip the list and start an instance directly with --instance <name> (e.g. --instance work), which is what an instance's own entries ("Claude (work)") do.
Instances other than Main are not registered to handle Claude's magic links. When logging in to another instance, use the "Use a login code instead" option to log in with a one-time code.
This is to make Cowork function. The app will block cowork if the application is not inside of C:\Program Files\WindowsApps, which requires admin permissions to be written to and read from. EDIT: This WAS to make Cowork function, but Anthropic has since removed the ability to run it locally. I may rework the launcher to remove the admin requirement in the future. But right now, I'd rather keep it all working.
This installer generates a modified version of the Claude Desktop client with extension support enabled. It creates a standalone installation that can coexist with the official Claude Desktop client, automatically keeping both the client and extensions up to date.
This can happen due to reasons I'm not really sure of. Restarting the application is enough.
Yep, Waca- etc are a pretty common false positive. Pyinstaller-built exes used to also trigger it. There isn't really anything I can do about that.
You might need to go to Settings -> Privacy and Security and click "Open anyway".
MacOS REALLY doesn't like apps that aren't notarized (aka, that haven't paid the 99$ apple tax). Not much I can do. I can't afford the subscription, and even if I could, this wouldn't be allowed on the app store.
On first launch, you might see a crash dialog about the network service. This is (likely) because the modified app needs Keychain permission to be granted, given that it uses an ad-hoc signature. Just ignore it.
Ubuntu 24.04 and newer block the sandbox Claude relies on unless the app has an AppArmor profile. The official package installs one for its own location, so the launcher adds one for its install. That needs root once, so you'll be asked for your password on the first launch. Other distros don't need this and won't ask.
If anything goes wrong, click Open logs in the launcher's window (it's there during the countdown and on errors). The log is launcher.log (or launcher-<name>.log for a named --instance) in %LOCALAPPDATA%\ClaudeWebExtLauncher on Windows, and in the launcher's data folder on macOS/Linux; the previous run's is kept as launcher.previous.log.
Running the launcher with --debug skips the window and shows everything in the terminal instead, with Claude attached to it so its own output is visible too.
On Windows there's a single (x64) download — no need to pick an architecture. On an ARM64 PC it detects the host and installs the native arm64 Claude automatically (Windows 11 on ARM).
Download the latest installer from Releases and run it. The installer will handle everything automatically.
On first run the launcher installs itself to a fixed place and runs from there from then on, so its shortcuts and updates always use the same path:
| OS | Installed launcher |
|---|---|
| Windows | %LOCALAPPDATA%\ClaudeWebExtLauncher\Claude_WebExtension_Launcher.exe |
| macOS | ~/Applications/Claude_WebExtension_Launcher.app |
| Linux | ~/.local/share/claude-webext-launcher/Claude_WebExtension_Launcher |
After that you can delete what you downloaded. Running a downloaded copy again simply hands over to the installed one, or replaces it first if the download is a newer version.
Open the launcher's settings (run it with --show-setup, or Launcher settings in the instance list) and click Uninstall…. On Windows it's also listed under Settings → Apps → Installed apps. Or run the launcher with --uninstall.
It removes the launcher, the patched Claude, the shortcuts and everything else the launcher set up (on Windows: the Cowork service, which needs one administrator prompt; on Linux: the AppArmor profile, which needs your password). Your instances' data (logins, settings and local sessions) is kept unless you tick the box to delete it. Cowork and Code sessions shared with the official Claude app are given back to it first.
On Linux, pick the linux-amd64 or linux-arm64 zip, extract it and run Claude_WebExtension_Launcher. The modified Claude and its extensions are kept in ~/.local/share/claude-webext-launcher too.
On first launch the launcher asks whether to add itself to the applications menu (the Start Menu on Windows) and whether to start when you log in. To change your mind later, run it with --show-setup to get the same screen again. Instances can have their own entries too, from the cog in the instance list (see Multi-instance).
On macOS the launcher itself is in your Applications folder (~/Applications) once it has run, so it only asks about starting at login. An instance's applications-menu entry is a small "Claude (name)" app next to it, which shows up in Launchpad and Spotlight and can go in the Dock.
On Linux, the launcher also registers itself for claude:// links, so magic-link login opens in the modified app.
The installer provides:
The installer only creates a local modified Claude Desktop installation. No data is collected or transmitted by the installer itself. Individual extensions may have their own privacy policies.
If you encounter issues:
58 followers · starred Jan 2026
1,621 followers · starred Nov 2025
165 followers · starred Aug 2025
Creates a separate Claude Desktop instance with support for Web Extensions
Go
209
136 commits
updated Oct 10, 2026
A custom installer for Claude Desktop that includes built-in extensions (and the ability to install your own).
Note: The extensions in question are Web extensions! Not to be confused with Local MCPs, which the client also calls Extensions and come in the dxt format.
Disclaimer: This is an unofficial, third-party modification of Claude Desktop that enables extension support. By using this installer, you acknowledge that:
You can run several copies of the client side by side, each with its own login, settings and sessions. Useful if you want multiple windows open, or if you have multiple accounts.
Turn on Manage multiple instances on the setup screen (shown on first launch, or with --show-setup). After its usual checks, the launcher then shows a list of your instances instead of launching straight away:
The instance you've been using all along is Main. Its data folder was called Claude-modified before; the launcher renames it to Claude-Main the first time it runs while that instance is closed. Instances you already had are added to the list automatically.
The launcher's own menu entry (plain "Claude Desktop (Extended)") opens the list. You can also skip the list and start an instance directly with --instance <name> (e.g. --instance work), which is what an instance's own entries ("Claude (work)") do.
Instances other than Main are not registered to handle Claude's magic links. When logging in to another instance, use the "Use a login code instead" option to log in with a one-time code.
This is to make Cowork function. The app will block cowork if the application is not inside of C:\Program Files\WindowsApps, which requires admin permissions to be written to and read from. EDIT: This WAS to make Cowork function, but Anthropic has since removed the ability to run it locally. I may rework the launcher to remove the admin requirement in the future. But right now, I'd rather keep it all working.
This installer generates a modified version of the Claude Desktop client with extension support enabled. It creates a standalone installation that can coexist with the official Claude Desktop client, automatically keeping both the client and extensions up to date.
This can happen due to reasons I'm not really sure of. Restarting the application is enough.
Yep, Waca- etc are a pretty common false positive. Pyinstaller-built exes used to also trigger it. There isn't really anything I can do about that.
You might need to go to Settings -> Privacy and Security and click "Open anyway".
MacOS REALLY doesn't like apps that aren't notarized (aka, that haven't paid the 99$ apple tax). Not much I can do. I can't afford the subscription, and even if I could, this wouldn't be allowed on the app store.
On first launch, you might see a crash dialog about the network service. This is (likely) because the modified app needs Keychain permission to be granted, given that it uses an ad-hoc signature. Just ignore it.
Ubuntu 24.04 and newer block the sandbox Claude relies on unless the app has an AppArmor profile. The official package installs one for its own location, so the launcher adds one for its install. That needs root once, so you'll be asked for your password on the first launch. Other distros don't need this and won't ask.
If anything goes wrong, click Open logs in the launcher's window (it's there during the countdown and on errors). The log is launcher.log (or launcher-<name>.log for a named --instance) in %LOCALAPPDATA%\ClaudeWebExtLauncher on Windows, and in the launcher's data folder on macOS/Linux; the previous run's is kept as launcher.previous.log.
Running the launcher with --debug skips the window and shows everything in the terminal instead, with Claude attached to it so its own output is visible too.
On Windows there's a single (x64) download — no need to pick an architecture. On an ARM64 PC it detects the host and installs the native arm64 Claude automatically (Windows 11 on ARM).
Download the latest installer from Releases and run it. The installer will handle everything automatically.
On first run the launcher installs itself to a fixed place and runs from there from then on, so its shortcuts and updates always use the same path:
| OS | Installed launcher |
|---|---|
| Windows | %LOCALAPPDATA%\ClaudeWebExtLauncher\Claude_WebExtension_Launcher.exe |
| macOS | ~/Applications/Claude_WebExtension_Launcher.app |
| Linux | ~/.local/share/claude-webext-launcher/Claude_WebExtension_Launcher |
After that you can delete what you downloaded. Running a downloaded copy again simply hands over to the installed one, or replaces it first if the download is a newer version.
Open the launcher's settings (run it with --show-setup, or Launcher settings in the instance list) and click Uninstall…. On Windows it's also listed under Settings → Apps → Installed apps. Or run the launcher with --uninstall.
It removes the launcher, the patched Claude, the shortcuts and everything else the launcher set up (on Windows: the Cowork service, which needs one administrator prompt; on Linux: the AppArmor profile, which needs your password). Your instances' data (logins, settings and local sessions) is kept unless you tick the box to delete it. Cowork and Code sessions shared with the official Claude app are given back to it first.
On Linux, pick the linux-amd64 or linux-arm64 zip, extract it and run Claude_WebExtension_Launcher. The modified Claude and its extensions are kept in ~/.local/share/claude-webext-launcher too.
On first launch the launcher asks whether to add itself to the applications menu (the Start Menu on Windows) and whether to start when you log in. To change your mind later, run it with --show-setup to get the same screen again. Instances can have their own entries too, from the cog in the instance list (see Multi-instance).
On macOS the launcher itself is in your Applications folder (~/Applications) once it has run, so it only asks about starting at login. An instance's applications-menu entry is a small "Claude (name)" app next to it, which shows up in Launchpad and Spotlight and can go in the Dock.
On Linux, the launcher also registers itself for claude:// links, so magic-link login opens in the modified app.
The installer provides:
The installer only creates a local modified Claude Desktop installation. No data is collected or transmitted by the installer itself. Individual extensions may have their own privacy policies.
If you encounter issues:
58 followers · starred Jan 2026
1,621 followers · starred Nov 2025
165 followers · starred Aug 2025
