The test file at https://github.com/mozilla/pdf.js/blob/master/test/pdfs/annotation-choice-widget.pdf contains listboxes, which are not rendered correctly when printed right now. These kinds of fields are made by https://github.com/mozilla/pdf.js/blob/master/src/display/annotation_layer.js#L672-L678.

/cc @calixteman 
this.defaultValue = data.defaultValue;
    this.doNotScroll = data.doNotScroll;
    this.doNotSpellCheck = data.doNotSpellCheck;
    this.delay = data.delay;
    this.display = data.display;
    this.doc = data.doc.wrapped;
    this.editable = data.editable;
    this.exportValues = data.exportValues;
    this.fileSelect = data.fileSelect;
    this.hidden = data.hidden;
    this.highlight = data.highlight;
    this.lineWidth = data.lineWidth;
    this.multiline = data.multiline;
    this.multipleSelection = !!data.multipleSelection;
    this.name = data.name;
    this.password = data.password;
    this.print = data.print;
    this.radiosInUnison = data.radiosInUnison;
    this.readonly = data.readonly;
    this.rect = data.rect;
    this.required = data.required;
    this.richText = data.richText;
    this.richValue = data.richValue;
    this.rotation = data.rotation;
    this.style = data.style;
    this.submitName = data.submitName;
    this.textFont = data.textFont;
    this.textSize = data.textSize;
    this.type = data.type;
    this.userName = data.userName;