Error fetching /index.json:

[jared-hexagon]

Summary

When I run Storybook 8.4.7 (with TypeScript and MDX) I get this warning in my CLI:

WARN 🚨 SyntaxError: Unexpected token ':'

This results in my index.json returning 500 error. Console:

SB_PREVIEW_API_0006 (StoryIndexFetchError): Error fetching `/index.json`:

SyntaxError: Unexpected token ':'

Full output:

@storybook/core v8.4.7

info Found existing addon "@storybook/addon-docs", skipping.
info Found existing addon "@storybook/addon-actions", skipping.
info Found existing addon "@storybook/addon-docs", skipping.
info Found existing addon "@storybook/addon-actions", skipping.
info => Starting manager..
info => Starting preview..
info Addon-docs: using MDX3
info => Using implicit CSS loaders
info => Using default Webpack5 setup
<i> [webpack-dev-middleware] wait until bundle finished
10% building 0/1 entries 0/0 dependencies 0/0 modulesWARN 🚨 SyntaxError: Unexpected token ':'
╭──────────────────────────────────────────────────╮
│                                                  │
│   Storybook 8.4.7 for react-webpack5 started     │
│   395 ms for manager and 1.11 s for preview      │
│                                                  │
│    Local:            http://localhost:8080/      │
│    On your network:  http://192.168.1.4:8080/    │
│                                                  │
╰──────────────────────────────────────────────────╯
info Found existing addon "@storybook/addon-docs", skipping.
info Found existing addon "@storybook/addon-actions", skipping.
<i> [webpack-dev-middleware] wait until bundle finished: /runtime~main.iframe.bundle.js
<i> [webpack-dev-middleware] wait until bundle finished: /vendors-node_modules_pnpm_ansi-html-community_0_0_8_node_modules_ansi-html-community_index_js-af89c3.iframe.bundle.js

I've looked through my codebase and can't find any erroneous code.

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