Allow spell checking in multiple languages

[crisidev]

Preflight Checklist

• I have read the Contributing Guidelines for this project.
• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Problem Description

It is not possible to spell check in multiple languages.

Proposed Solution

It would be nice to be able to have the spell checking working for multiple languages.

Alternatives Considered

I have tried to change the preferences file to see if this is just a UI enhancement, but manually adding languages in the preference files never actually activates them.

See https://www.reddit.com/r/ferdium/comments/1g82pnt/spellcheck_in_multiple_languages/

Additional Information

No response