Would be useful for those of us who think fast and type faster.
This is an interesting idea. The question is how to implement it.
There is no smf extension to do this and we unfortunately have no web dev willing to do this.
using spellingcow.com, a seemingly commercial third party service.
Of course, sending all strings to their service is unacceptable for privacy reasons. However, the concept is nice nonetheless.
Is there a Free Software spellingcow alternative? One that we could locally install on whonix.org?
In meanwhile, why trust whonix.org, why not use the local spell checker built into your browser?
By the way, to avoid fingerprinting your keyboard layout (by whonix.org server which does not stand in a developers home, therefore should not be trusted, and it should not depend on trust anyway), on https://www.whonix.org/wiki/Surfing_Posting_Blogging we advise to type in an external editor such as kwrite (which also supports spell checking), not in browser.
Your browser doesn’t automatically underline misspelled words in text boxes for you?