Spell check

Spell check currently only supports English.

Where to find it

Setting: Preferences › Spell check Off by default.
Menu: Spelling › Check spelling & grammar The same toggle, checked when on.
Menu: Spelling › Edit dictionary… Add or remove your own words.

Turning it on

Spell check starts off. Switch it on from Preferences, or from the Spelling menu, and it applies immediately in both the visual and source editors.

Adding your own words

Click a flagged word for suggestions and an Add to Dictionary button, or manage the whole list from Spelling › Edit dictionary…. Added words apply across every project you open, not just the current one.