Dictation in mail app not working

Function key 6 aka. Fn 6 Activates voice input and dictation everywhere but not in Mac Mail. Notes and Thunderbird allow me dictate input text but not Mail. After a restart it may work once but not after that.

On the Edit menu Fn D is listed as the start dictation option. This worked for me indicating that all the other speech to text infrastructure is working.

Turns out this was a Function key shortcut conflict Fn 6 is listed as the bring floating window to the front shortcut ( according to google look up ). Using Fn D seems to be the answer in Mail ?

Question is how to change the Function key shortcuts in Mail to have Fn 6 start diction.