@Pathduck Thank you for the workaround! My professor running a WeBWorK website also encounters a similar issue where the redirect is "insecure".
Purpose of this response is to future readers; when you right click on the link, click "Save Link As...", and choose a directory to save the file to, there is a noticeable amount of time that will pass before the prompt to "Discard" or "Keep" appears in the "Downloads" tab. That time that passes seems to only happen once as when I attempt to recreate & time this delay, it hasn't happened again.
Thank you again for your speedy response @Pathduck !