Hi, could you walk me through the original problem? Here's what I think you're saying: (1) On the Settings page, Portable Document Format (PDF) was set to "Open in Firefox" With this setting, Firefox opens PDF in a tab, it shows the original HTTPS or HTTPS address in the address bar, and it stores the PDF in the web content cache instead of in the Downloads folder. (2) When you click the Download button on the PDF viewer's toolbar, Firefox 98+ should show a file browsing dialog -- it works like "Save Page As..." (Ctrl+S). Is that the dialog which is blank or closing itself immediately?