The following code is flagged as dead (since it's *replacing* rather than updating the existing Object):
https://github.com/mozilla/pdf.js/blob/4483cba72410027acf46630ebf252ae529704476/src/core/xfa/template.js#L2336-L2339
according to the alert in https://github.com/mozilla/pdf.js/security/code-scanning/103?query=ref%3Arefs%2Fheads%2Fmaster

Looking at the surrounding code, I can see a couple of possibilities here:
 1. This is indeed just dead code, which should be removed.
 2. The code should be moved up, and placed just *above* the previous block instead.
 3. There should be other, more invasive, changes made to this code...

/cc @calixteman Which solution is correct here?
Assuming it's either option 1 or 2, I can submit a patch to fix this.
caption.attributes.class[0] = "xfaCaptionForCheckButton";
    }
    if (!ui.attributes.class) {
      ui.attributes.class = [];
    }
    ui.children.splice(0, 0, caption);
    switch (this.caption.placement) {
      case "left":
        ui.attributes.class.push("xfaLeft");
        break;
      case "right":
        ui.attributes.class.push("xfaRight");
        break;
      case "top":
        ui.attributes.class.push("xfaTop");
        break;
      case "bottom":
        ui.attributes.class.push("xfaBottom");
        break;
      case "inline":
        
        ui.attributes.class.push("xfaLeft");
        break;
    }
    this.w = savedW;
    this.h = savedH;
    return HTMLResult.success(createWrapper(this, html), bbox);
  }
}
class Fill extends XFAObject {