css - XMLNS W3 URL for SVG spec now throwing error in Chrome

Question

I used this SVG mask for grayscale in browsers where filter: grayscale(100%) doesn't work:

filter: url("data:image/svg+xml;utf8,<svg version='1.1' xmlns='http://www.w3.org/2000/svg' height='0'><filter id='greyscale'><feColorMatrix type='matrix' values='0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0' /></filter></svg>#greyscale");

A little while back, this worked perfectly fine, but now I get this error in console:

Unsafe attempt to load URL data:image/svg+xml;utf8,http://www.w3.org/2000/svg' height='0'>#greyscale from frame with URL [my domain here]. Domains, protocols and ports must match.

Needless to say, the grayscale filter no longer works.

1. Can you explain what is going wrong?
2. Can this be fixed so that same CSS code is used, no error is thrown, and the filter works?
3. Considering it mentions same domain and protocol, though I don't know how to implement the solution as I don't understand the problem, I am able to put and link files on the same domain/subdomain with same protocol, instead of using external URL.

UPDATE:

User @Potherca commented:

...worked in Chrome 52, broke in Chrome 53...

This is also my experience. The SVG mask doesn't work in current version of Chrome (Chrome Version 53.0.2785.116) but it worked in previous version. It does still work in Firefox and Safari.

UPDATE 2: I tried it with https like ...xmlns='http://www.w3.org/2000/svg'... but error / bug persists.

UPDATE 3: As user @Potherca suggested, moving the SVG filter line to the top of the list of cross-browser filter rules eliminates the bug. NOTE: this is a workaround, but the main bug still exists in Chrome/Safari/webkit, but not in other browsers/kits at the time of this update.

Answer 1

I had a similar issues. For cross-browser support several filter lines were added in the CSS.

It seemed to be caused by the SVG filter being the last in line. By moving it up before other filter lines Chrome used another filter and the error disapeared.

.gray-out {
    -webkit-filter: grayscale(100%);
    filter: grayscale(100%);
    filter: gray;
    filter: url("data:image/svg+xml;utf8,<svg>...</svg>");/* Move this line up */
}