Yarn error installing real-time-collaboration and/or watchdog plugin on stable branch

[DeltekDavid]

📝 Provide detailed reproduction steps (if any)

1. Clone the ckeditor5 repo per the "Prepare Editor Build" real-time collab docs.
2. Check out the stable branch.
3. Switch to ckeditor5/packages/ckeditor5-build-classic and run yarn. (The docs say to use npm, but it results in errors; yarn will install successfully.)
4. Try to install the plug-ins needed for real-time collab, again using yarn equivalent of the npm commands in the docs: yarn add --dev @ckeditor/ckeditor5-real-time-collaboration @ckeditor/ckeditor5-watchdog

✔️ Expected result

Packages install successfully.

❌ Actual result

An error appears, whether you add both packages at once OR do them individually (in either order).

error Invariant Violation: expected workspace package to exist for "glob"
    at invariant (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:2318:15)
    at _loop2 (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:91560:9)
    at PackageHoister.init (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:91619:19)
    at PackageLinker.getFlatHoistedTree (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:48551:20)
    at PackageLinker.<anonymous> (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:48562:27)
    at Generator.next (<anonymous>)
    at step (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:310:30)
    at C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:328:14
    at new Promise (<anonymous>)
    at new F (C:\Users\myusername\AppData\Roaming\nvm\v21.7.3\node_modules\yarn\lib\cli.js:5539:28)
info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.

❓ Possible solution

Was able to install the plug-ins via npm after using yarn to install the main packages. It's a bit confusing, since the docs use npm but the devs use yarn.

📃 Other details

• Tried clearing out ckeditor5/node_modules and running a fresh yarn install before adding the plug-ins.
• OS: Windows 10
• First affected CKEditor version: 41.3.1
• Node version: 21.7.3
• Installed CKEditor plugins: None (errors trying to install Real-Time-Collab and Watchdog)

---

If you'd like to see this fixed sooner, add a 👍 reaction to this post.

[Witoso]

Noted! We are rewriting this doc with the #15502, and predefined builds and cloning setup will be discouraged and not shown. This whole setup is confusing, so apologies. The best way is to use the online builder, or to use the bleeding-edge alphas which just work.