My wife has over 12k Pinterest pins and there are many that resolve to 404 errors. I thought it would be simple to just create a chrome extension she could run that would get the pins, then I would test the URLs for 404 errors and then perform a delete.

Creating the plugin wasn't difficult but of all things, I am getting hung up on being able to determine whether the remote URL is a 404 due to CORS issues. Using fetch with a mode of no-cors does not error but it doesn't return me anything that I can use to determine whether the link is valid or not. I understand the purpose of CORS, but I'm just surprised that there isn't a way to tell from javascript whether or not a domain is valid.

I've seen some approaches where it was stated to use a proxy which I guess you append the headers with, however I thought I would see if there was any creative means of telling whether an endpoint is even existent or not. I'm really only interested in capturing the broken links so I can then go about deleting the pins programmatically. I was going to go about testing whether I could use an iframe to assign src to the url and see if I'm able to extract any more info that way, but figured I would post here to see if there are any other creative approaches. I also tried performing a fetch for favicon.ico, thinking it would get around CORS due to it being an image and not the full page, but this didn't work as well as I was hoping.

If you have any ideas, please let me know. Thanks!