Stylelint is a css linter: https://stylelint.io/
As part of this change we have added two javascript scripts:
```
pnpm lint:css
pnpm lint:css:fix
```
Look at `.vscode/settings.json.sample` and `.vscode/extensions.json` for
configuration in VSCode.
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Co-authored-by: Joffrey JAFFEUX <j.jaffeux@gmail.com>
A few follup changes after changing to the chat footer split for drawer:
* Fixing a bug that stretched the unread indicator on mobile
* Minor style changes in hover/focus behaviour for chat drawer
* Repositioning of unread indicator so it has more space at the top of the footer
* Using the `c-unread-indicator` mixin
Adds a placeholder image + CTA in chat, for empty channel and DM lists.
On desktop with drawer mode, we split chat into tabs (like mobile).
---------
Co-authored-by: Joffrey JAFFEUX <j.jaffeux@gmail.com>
Co-authored-by: David Battersby <info@davidbattersby.com>
Co-authored-by: Régis Hanol <regis@hanol.fr>
