How to disable spell-checking and auto-correction in Skype?

In the new Skype there is currently no user switch. But you can go to:

C:\Program Files (x86)\Microsoft\Skype for Desktop\resources\app.asar.unpacked\node_modules\@paulcbetts\spellchecker\build\Release

and rename there the spellchecker.node file to something like disable__spellchecker.node__disable.

Then restart the Skype and the auto correction feature will be disabled.

note: This fix may be need to be applied again after update.