### Breaking changes

The `themeClass` function and ``-style selectors in themes are no longer supported (prefixing with `cm-` should be done manually now).

Themes must now use `&` (instead of an extra `$`) to target the editor wrapper element.

The editor no longer adds `cm-light` or `cm-dark` classes. Targeting light or dark configurations in base themes should now be done by using a `&light` or `&dark` top-level selector.