Selenium problems with PDF download in Firefox
问题 I'm working on an upgrade of our internal Java Selenium framework to the latest version 3.14.0 in combination with Firefox 61.0 and Geckodriver 0.21.0. I face problems when it comes to an automated download of a PDF file with Firefox. For example at this link there is a download button where I can let selenium perform a click on. Instead of downloading the pdf, a built-in viewer will be opened. The preference pdfjs.disabled should deactivate the viewer so created the driver instance with a