Purpose of the crossorigin attribute…?

Question

In both image and script tags.

My understanding was that you can access both scripts and images on other domains. So when does one use this attribute?

Is thi

Answer 1

I've found out how to persuade Google Chrome to allow file:// references without throwing a cross-origin error.

Step 1: Create a shortcut (Windows) or the equivalent in other operating systems;

Step 2: Set the target to something like the following:

"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --allow-file-access-from-files

That special command line argument, --allow-file-access-from-files, tells Chrome to let you use file:// references to web pages, images etc., without throwing cross-origin errors every time you try to transfer those images to an HTML canvas, for example. It works on my Windows 7 setup, but it's worth checking to see if it will work on Windows 8/10 and various Linux distros too. If it does, problem solved - offline development resumes as normal.

Now I can reference images and JSON data from file:// URIs, without Chrome throwing cross-origin errors if I attempt to transfer image data to a canvas, or transfer JSON data to a form element.