Using the wowinterface web UI to add a file to my addon (BastionEPGP in this occasion) I'm greeted with a cloudflare captcha, after I pass the captcha, wowinterface responds with
Cannot edit file - No ID was specified!
Chrome based browser.
Edit to add, just to make sure it's not interference from a browser plugin I disabled both plugin and built-in blockers.
I had to increase some settings on our firewall with cloudflare due to ddos attacks last night. I just backed off on a few of the settings that I think may have broken this for you.