Both the C/C++ and Python extensions seem to be open source, but I think you’re right about the remote development one.
https://github.com/Microsoft/vscode-cpptools https://github.com/Microsoft/vscode-python
https://github.com/Microsoft/vscode-cpptools https://github.com/Microsoft/vscode-python
There are alternative non Microsoft language servers for C++ and probably other languages which are fully open source and can be used in open source VSCode builds. But unfortunately some extensions depend specifically on the Microsoft language support extensions. For example Platform IO can't be published on OpenVSX due to this. https://github.com/platformio/platformio-vscode-ide/issues/1... . Similar with Unity debugger extension depending on microsoft C# extension.
Having some of the telemetry removed in VSCodium doesn't automatically remove it from the microsoft extensions. Taking into account that the official way for disabling telemetry in microsoft extensions depend on the telemetry setting in VSCode itself, having unsupported(and forbidden by microsoft license terms) combination of extension with vscodium seems like higher chance of disabling mechanism partially failing.
As for PlatformIO, luckily at least the project compilation and toolchain setup (which is the most important part of PlatformIO) can be done with commandline tool independently of any editor extension.
https://github.com/microsoft/pylance-release/issues/4#issuec...