On the Desktop app
You can activate or deactivate spell check in Slite via the top menu bar. Select Edit > Spellcheck.

On Chrome
Click the menu button in the top right of the browser toolbar and select Settings.
From there, click on Advanced > Languages > Add a language.
Make sure the spellcheck is toggled to "On" in the settings (indicated by blue color with the circle pushed to the right of the bar.)
