Check to make sure it is not due to a browser setting. Usually, when I have seen spell check while working in Canvas, it is the browser performing the check.
- Click the three-dots menu (Customize and control Google Chrome) in the top-right corner of the browser window.
- Select Settings.
- In the settings menu, click on Languages or search for it.
- Locate the Spell check setting and turn the toggle to the off position.
- Click the three-dots menu (Settings and more) in the top-right corner.
- Select Settings.
- In the Settings menu, go to Languages or search for "Typing".
- Find the setting for "Autocorrect misspelled words" and disable the toggle.
- Click the hamburger menu (three horizontal lines) in the top-right corner.
- Select Options or Preferences.
- Scroll to the Language section.
- Look for an option like "Check my spelling as I type" and uncheck it.
See if that fixes the issue first and report back if those are all turned on so we can look for another option.