>>1483514Ok bro listen I have a prototype. It's still early stuff but it works. I need to find a way to download files in the background and zip them so the user is shown a single "Save As" dialog.
Now, the way it works right now is the script simply downloads them in the background and they get saved to your default download folder (whatever it is on your browser). I tried it on the page you linked and it "successfully" downloads 60 items but because I'm obviously not logged into the board, the files are just .html pages asking me to sign in.
To try it, go to the page and click on the Tampermonkey icon -> Create new script, just paste the script and click save. Now when you visit threads on that board a "Get Links" button will appear at the bottom left (I just put this thing together in a hurry I have no time to design a comfy user interface). When you click it it will start to download files, no dialog will appear (but you can set the askSaveLocation variable to true if you want that). I will try to look for a way to download the files in the background and zip them before you save them.
User script:
https://pastebin.com/raw/Baiw3CwKI'm curious to see if it does work when you're actually logged into the board. Give it a try and let me know.