VSCodium defaults to the Open VSX Registry instead of Microsoft's official marketplace. While Open VSX is great, sometimes an extension you need for work or study (or if you want to use official extensions risk-free) is only available on the official VS Code marketplace. I created a small extension for switching between the two marketplaces. check -
https://open-vsx.org/extension/AbdulOhab/source-swap Source Code:
https://github.com/AbdulOhab/vscodium-source-swap