I recently ran into an issue where after several clients upgraded to Safari 13 began seeing boxed question marks everywhere. No text, only question marks. I ran across this article in the apple community which corrected my issue.
https://discussions.apple.com/thread/250422454
Hi @dstaubitz
I think what you are seeing is described in this link.
I have seen this in my environment on some devices.
https://www.jamf.com/jamf-nation/discussions/27532/font-issues-boxed-question-marks
In our instance, we found that an updated version of "FiraCode" font caused the problem. We deleted the font and the problems went away. We dug deeper into it and discovered that the creator of that font updated it recently and only users who obtained the font within the past few months saw the problem. Older versions of the font were unaffected.
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