VSCode slow in your Codespace? It might be Alpine

The problem

I have a Github Codespace, built on a custom Docker container, and it is slow. Well, VSCode in that Codespace is slow. The Codespace VM itself works fine - I can use the command line normally, but the in-browser VSCode instance tied to it is so sluggish, it just doesn't work. Portforwarding doesn't start, extensions don't loaded, even the Git integration in VSCode failed to start, stuck on a "Scanning folder for git repositories�" message.

This was especially frustrating because I couldn't find anything on Github or the internet about general outtages or performance issues with Codespaces workspaces or VSCode.

What's going wrong

It's difficult to be certain, but this ticket hints that older versions of Alpine or packages tied to Alpine, like Git, might not work with newer versions of VScode. In my case, my codespace container was built on Alpine 3.12.

The (sort of) solution

A new base container from Alpine 3.19 later, I recreated my Codespace, and VScode was zippy again. The problem with this of course is that my toolchain is dependent on Alpine 3.12 because tool runtimes are version locked to 3.12, and this is why I don't like tooling in Alpine.

Anyway, that's its own issue. This post is here on the off chance someone is Googling this issue in frustration - hope it helped you.