Computer: iMac running Sierra, Universal Type Client 6 Problem: Safari and Mail show question marks in place of text. Looks like: ⍰⍰⍰⍰ ⍰⍰⍰⍰ ⍰⍰ ⍰⍰⍰⍰⍰⍰⍰ ⍰⍰⍰⍰⍰ ⍰ ⍰⍰ ⍰⍰⍰⍰ ⍰⍰⍰⍰ ⍰⍰⍰⍰ ⍰⍰⍰⍰⍰⍰ ⍰⍰⍰⍰⍰⍰ ⍰⍰ Attempted solutions: Clear font cache in UTC: computer restarts, problem is gone…for a short time. Returns within minutes. Deactivate various fonts in Font Book: problem is gone…for a short while. Returns again. Run Onyx (https://www.titanium-software.fr/en/index.html which includes clearing the font cache. Problem is gone…returns again after a short time. There seems to be some process, program or action that is activating a font that is conflicting with something in WebKit (whatever that is…I’m getting this from having read other posts). But I am not sure as to how to locate that suspect action, identify what font is conflicting, reduce system fonts, disable Font Book, or other steps specifically related to Sierra. Any help would be appreciated. We have 4 or 5 other machines running Safari and UTC 6 without any trouble. I’m not sure why just this one machine is having so much trouble.