The file in question is: https://ia802606.us.archive.org/7/items/fiftyyearsinwall00clewuoft/fiftyyearsinwall00clewuoft.pdf which is 78 MB. It downloaded OK, but clicking on the "Download" button does nothing for about five minutes, and the dialog box "Opening <filename>" with the Save As option is still on my screen but grayed-out ten minutes later. In fact, it's overlaying this tab because it's always on top. Programming errors here: Click on "Download" produces no response, not even a spinner. It should say "Rendering file", or whatever it is doing, and show a progress bar. The time spent is unacceptable. We have gigahertz processors, remember? "Save As" doesn't save the file, at least not so far. What is the problem? What is it doing? Why no message? A dialog box from one tab should not show on top of another tab. Clicking twice on "Download" (because there's no indication the first click registered) should not open two dialog boxes, especially not one exactly on top of the other.