So those characters where entered into ACf to set up the fields and when they’re exported to PHP they are listed as unprintable. This is only a guess, but I’d say it has something to do with either the way they are entered, displayed during the export or copied and pasted into PHP.
It could also be something to do with the theme check plugin. It’s showing these as 2 unprintable characters when they are more than likely a single character.
I tried searching for additional information, but wasn’t able to find anything.
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