I am using Pro and Arcade scripting for creating labels. We have a field set aside for labels.
$feature.MBLABEL
The script looks like
"<fnt size= '8'>" + $feature.MBLABEL + "</fnt>"
For each and every label it works fine. However, if there is an Ampersand in the MBLABEL field it does not
Example the Text String in the field is "Cooperative Light & Power HQ"
The below image shows how it breaks the label. Removing the Ampersand fixes the issue.

Is this a known issue with Arcade?
Removing the <fnt> scripting fixes it as well. But then why bother with Arcade at all.