Spell check not working as expected

Initial setup
1

I’ve recently installed eM client - version 10.1.4828 onto a mac running Sonoma. Everything is great except … spell check isn’t flagging misspellings as I type. Under the Tools menu, “Use Automatic SpellCheck” is checked and my settings/preferences have “use automatic spell check” checked and “language” as English (United States) for Default Spell-Checker Settings, Mail Spell-Checker, and Chat Spell Checker. (And I setting it to French and mis-spelling things in French and that didn’t work either.)
If I run “check spelling” it works, but I’d like a red squiggle under bad text!

Help? Any suggestions?

2

Ah. Support has informed me that they don’t have spell-check for Mac because macOS already has autocorrect built-in.

3
4

Turns out that eM Client support may have been misinformed: Typing:
write -g NSAllowContinuousSpellChecking -bool true
into terminal resolved it.