I know almost nothing about this sort of thing, but I have managed to do what you’re describing without an add-on. Go to where you go in the cloud to download. Open your browser console (Ctrl+Shift+C or F12) and go to the Networking tab. Filenames will appear in the Networking tab as you interact with the cloud through the browser. If you right-click on a Filename, a dialogue box for it will open. The first option is Copy Value, which will open a sub-menu that includes Copy as cURL. This option copies everything that your browser sent to the cloud (to get the file you right-clicked) to your clipboard as a cURL command, which you can then paste into a bash script.

This won’t work for every cloud provider, but it does for some. Add-ons can be convenient, but there’s something to be said for “popping the hood,” so to speak. Good luck!