Even though we do not pass the telemetry build flags (and go out of our way to cripple the baked-in telemetry), Microsoft will still track usage by default.
We do however set the default `telemetry.enableCrashReporter` and `telemetry.enableTelemetry` values to false. You can see those by viewing your VSCodium settings.json and searching for `telemetry`.
The instructions [here](https://code.visualstudio.com/docs/supporting/faq#_how-to-disable-telemetry-reporting) and [here](https://code.visualstudio.com/docs/supporting/faq#_how-to-disable-crash-reporting) help with explaining and toggling telemetry.
It is also highly recommended that you review all the settings that "use online services" by following [these instructions](https://code.visualstudio.com/docs/getstarted/telemetry#_managing-online-services). The `@tag:usesOnlineServices` filter on the settings page will show that by default:
__Please note that some extensions send telemetry data to Microsoft as well. We have no control over this and can only recommend removing the extension.__ _(For example, the C# extension `ms-vscode.csharp` sends tracking data to Microsoft.)_
When searching the `@tag:usesOnlineServices` filter, note that while the "Update: Mode" setting description still says "The updates are fetched from a Microsoft online service", VSCodium's build script [sets the `updateUrl` field](https://github.com/VSCodium/vscodium/blob/master/prepare_vscode.sh#L36) in `product.json` to that of VSCodium's own small [update server](https://github.com/VSCodium/update-api), so enabling that setting won't actually result in any calls to Microsoft servers.
Likewise, while the descriptions for "Extensions: Auto Check Updates" and "Extensions: Auto Update" include the same phrase, VSCodium [replaces](https://github.com/VSCodium/vscodium/blob/master/prepare_vscode.sh#L42) the Visual Studio Marketplace with Open VSX, so these settings won't call Microsoft, either.
The `product.json` file is set up to use [open-vsx.org](https://open-vsx.org/) as extension gallery, which has an [adapter](https://github.com/eclipse/openvsx/wiki/Using-Open-VSX-in-VS-Code) to the Marketplace API used by VS Code. Since that is a rather new project, you will likely miss some extensions you know from the VS Code Marketplace. You have the following options to obtain such missing extensions:
* Ask the extension maintainers to publish to [open-vsx.org](https://open-vsx.org/) in addition to the VS Code Marketplace. The publishing process is documented in the [Open VSX Wiki](https://github.com/eclipse/openvsx/wiki/Publishing-Extensions).
* Create a pull request to [this repository](https://github.com/open-vsx/publish-extensions) to have the [@open-vsx](https://github.com/open-vsx) service account publish the extensions for you.
* Download and [install the vsix files](https://code.visualstudio.com/docs/editor/extension-gallery#_install-from-a-vsix).
* Modify the `extensionsGallery` section of the `product.json` file in your VSCodium installation to use the VS Code Marketplace as shown below. However, note that [it is not clear whether this is legal](https://github.com/microsoft/vscode/issues/31168).
The debugger provided with Microsoft's [C# extension](https://github.com/OmniSharp/omnisharp-vscode) as well as the (Windows) debugger provided with their [C++ extension](https://github.com/Microsoft/vscode-cpptools) are very restrictively licensed to only work with the offical Visual Studio Code build. See [this comment in the C# extension repo](https://github.com/OmniSharp/omnisharp-vscode/issues/2491#issuecomment-418811364) and [this comment in the C++ extension repo](https://github.com/Microsoft/vscode-cpptools/issues/21#issuecomment-248349017).
A workaround exists to get debugging working in C# projects, by using Samsung's opensource [netcoredbg](https://github.com/Samsung/netcoredbg) package. See [this comment](https://github.com/VSCodium/vscodium/issues/82#issue-409806641) for instructions on how to set that up.
Like the debuggers mentioned above, some extensions you may find in the marketplace (like the [Remote Development Extensions](https://code.visualstudio.com/docs/remote/remote-overview)) only function the offical Visual Studio Code build. You can work around this by adding the extension's internal ID (found on the extension's page) to the `extensionAllowedProposedApi` property of the product.json in your VSCodium installation. For example:
VSCodium (and a freshly cloned copy of vscode built from source) stores its extension files in `~/.vscode-oss`. So if you currently have Visual Studio Code installed, your extensions won't automatically populate. You can reinstall your extensions from the Marketplace in VSCodium, or copy the `extensions` from `~/.vscode/extensions` to `~/.vscode-oss/extensions`.
You can follow the [Portable Mode instructions](https://code.visualstudio.com/docs/editor/portable) from the Visual Studio Code website.
- **Windows** / **Linux** : the instructions can be followed as written.
- **macOS** : portable mode is enabled by the existence of a specially named folder. For Visual Studio Code that folder name is `code-portable-data`. For VSCodium, that folder name is `codium-portable-data`. So to enable portable mode for VSCodium on Mac OS, follow the instructions outlined in the [link above](https://code.visualstudio.com/docs/editor/portable), but create a folder named `codium-portable-data` instead of `code-portable-data`.
There is an external Gentoo overlay with a working ebuild to install VSCodium, provided by [@wolviecb](https://github.com/wolviecb/). The overlay can be found [here](https://github.com/wolviecb/overlay).
