"fi" screen display changing to small text
Whenever I type "fi" in some apps – mail for one – it is autocorrected to a small symbol, maybe a subscript.Here it is pasted from mail: fi This is also true for screen text display. I first noticed it with Facebook earlier today. True both for text I am entering, like "first" where the fi will be replaced by this tiny symbol. Have tried the software keyboard (through system prefs) with same result. Not happening here, but is happening on various web sites on Safari though not on Chrome or Firefox.
Any ideas?
Thank you
I'm on a MacBook Pro 2015 (15") in current Sierra (10.12.1)