The Spellcheck dialog has a button for ignoring selected words, but it's not possible to clear the ignored words list from the dialog itself. If we want to reset the ignored words list we need to:
- Close the Spellcheck dialog
- Use the "Clear Ignored Words" action in the menu
- Reopen the Spellcheck dialog
Adding a button "Clear Ignored Words" button into Spellcheck dialog would be more handy and made to have all the actions relative to spellcheck into the dialog.