Unable to get storybook to build with storybook-rsbuild.

[edhgoose]

Hi,

Since adding storybook-rsbuild, I've found that I'm unable to get a build to complete.

The process always gets stuck on:

● Client ━━━━━━━━━━━━━━━━━━━━━━━━━ (70%) sealing chunk optimization

If I run it in dev mode, the iframe.html never loads - and sits in pending.

The UI shows:

start   Compiling...

The full output, for build:

$ yarn run build:storybook
@storybook/cli v7.6.19

info => Cleaning outputDir: /.storybook/dist
info => Loading presets
info => Building manager..
info => Manager built (582 ms)
info => Building preview..
info Addon-docs: using MDX3
info => Copying static files: /Users/ed.hartwellgoose/my-company/node_modules/@storybook/manager/static at /Users/ed.hartwellgoose/my-company/frontend/.storybook/dist/sb-common-assets
warn    Rsbuild plugin "rsbuild:less" registered multiple times.
● Client ━━━━━━━━━━━━━━━━━━━━━━━━━ (70%) sealing chunk optimization

For dev:

$ yarn run storybook
Initializing the Mock Service Worker at "/Users/ed.hartwellgoose/my-company/frontend/.storybook/dist"...

Service Worker successfully created!
/Users/ed.hartwellgoose/my-company/frontend/.storybook/dist/mockServiceWorker.js

Continue by creating a mocking definition module in your application:

https://mswjs.io/docs/getting-started/mocks

@storybook/cli v7.6.19

info => Serving static files from ././.storybook/dist at /
info => Starting manager..
info => Starting preview..
info Addon-docs: using MDX3
warn    Rsbuild plugin "rsbuild:less" registered multiple times.
╭─────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│                                                                                                         │
│   Storybook 7.6.19 for /Users/ed.hartwellgoose/my-company/node_modules/storybook-react-rsbuild started   │
│   1.18 s for manager and 1.61 s for preview                                                             │
│                                                                                                         │
│    Local:            https://localhost:8082/                                                            │
│    On your network:  https://my-company.dev:8082/                                                        │
│                                                                                                         │
│   A new version (8.1.6) is available!                                                                   │
│                                                                                                         │
│   Upgrade now: npx storybook@latest upgrade                                                             │
│                                                                                                         │
│   Read full changelog: https://github.com/storybookjs/storybook/blob/next/CHANGELOG.md                  │
│                                                                                                         │
╰─────────────────────────────────────────────────────────────────────────────────────────────────────────╯
start   Compiling...

The terminal looks like it's running esbuild when it gets stuck.

I've tried running with various debug options, e.g. --debug or --loglevel silly, but it provides nothing new which puzzles me.

Any clues or points as to what might be the issue? Or what information would help with debugging?

Thanks, Ed