Export WebMap bug when FeatureLayer is symbolized by Arcade expression

[Jay_Gregory]

I have been having great success using the Python API to export web maps to PDFS on Portal 10.6

However, I'm running into this strange issue that whenever I add a FeatureLayer to my web map and then symbolize the feature layer by an Arcade expression, the web map doesn't print the layer.  It prints the other layers in the web map, but not the feature layer symbolized by the Arcade expression.  However, I am able to correctly print the web map using the print tool within the map viewer itself - however, I'm more interested in automating the printing of web maps.  

Anyone else running into this issue?

[Jay_Gregory · Accepted solution]

Turns out if the Arcade Expression uses single quotes, the export map tool won't work, but if it uses double quotes, it will.