Thanks for reaching out to Jotform Support. The Settings or Gear icon is supposed to show on the right side of the PDF Editor, as shown in the screenshot below:
Can you share with us the URL of the form that you're working on? Let me show you where to find the form URL:
On your My Forms page, hover your mouse over the form and click on More on the right side of the page.
Under the Publish column, select Publish Form.
Click on the Copy Linkbutton.
Once we hear back from you, we'll be able to help you with this.