Flexible Haskell - a new plugin for JetBrains IDEs

As the process of adding a Beta channel wasn’t clear to me, here’s a how-to:

1. open the Plugins dialog

2. Click the settings icon (the cog wheel) and click Manage Plugin Repositories…

3. Add https://plugins.jetbrains.com/plugin/30630-flexible-haskell/versions/beta

The plugin will now install from the Beta channel.