CreateCheckBox example draws too large, clipped checkmark

I am using the example code from CreateCheckBox of v2.0.23 to create a PDF with a rendered checkbox (https://github.com/apache/pdfbox/blob/2.0.23/examples/src/main/java/org/apache/pdfbox/examples/interactive/form/CreateCheckBox.java). Regardless of whether I use the original code or change .unCheck() to .check(), the checkmark drawn in the PDF (when the checkbox is checked) is too large and gets clipped (see attached image).

I tried the latest Adobe Reader version and other PDF viewers as well as drawing into a different, pre-existing PDF document. The issue remains. In case it is relevant, I receive the following output when executing the code:

Mai 17, 2021 10:51:17 AM org.apache.fontbox.ttf.CmapSubtable processSubtype14
WARNING: Format 14 cmap table is not supported and will be ignored