VS Code plugin stopped finding references - Regression - Svelte 3

[benbucksch]

Describe the bug

Since a few weeks, my VS Code doesn't find code references anymore.

Reproduction

• Open a project that uses Svelte 3
• Go to any TypeScript class defined in a .ts file
• Right click on a class property, function, enum value or similar
• Select menu item "Find all references" (Alt-Ctrl-F12)

Actual result

• VS Code finds references, so it appears to work, but they are only from the TypeScript files
• None of the references in .svelte files are found
• This means that I am regularly breaking my code during refactoring, because I am not seeing all instances of the identifier.

Expected behaviour

• VS Code finds all references, without exception, including in Svelte files

Regression

• I am positive that this worked correctly, not too long ago (a few weeks, maybe 1-2 months).
• I don't know when exactly it regressed and when I updated the VS Code plugin

Non-solution

• Upgrade to Svelte 5 is not an option.

System Info

• OS: Ubuntu 24.04
• IDE: VSCodium
• The project is currently using Svelte 3.55.1.
• Parula is a major application of the size of Microsoft Outlook, Teams, of Thunderbird, with a corresponding code size and complexity, and depends entirely on Svelte for the UI, so even a mild upgrade to Svelte 4 is very risky.

Which package is the issue about?

Svelte for VS Code extension

[itzTheMeow]

I noticed this occurs on my Svelte 3 project. The entire Svelte Language Server seems to fail. I can't autocomplete or format files either.
Downgrading the extension from 109.6.0 to 109.5.4 fixes the issue.

[jasonlyu123]

We recently changed the logic to exclude "solution" project, the tsconfig with project references and files: []. This problem is that this logic depends on TypeScript's internal behaviour, and it doesn't work in TypeScript <5.7. The workaround for now is not using the workspace version of TypeScript.

The change was introduced in 109.4.0. @itzTheMeow, your problem shouldn't be the same issue. Please open a new issue with a reproduction.