XYZ Layer in Open Layers has Missing Tiles

Question

In Open Layers I'm having a missing tile problem where it generates a missing link icon and a pink background. I found several threads including this one saying to add this code OpenLayers.Util.onImageLoadError = function() {this.src = '/img/blank.png';};

Sorry if this is dumb, but should my blank.png just be a 1px transparent png24? And also where should the img folder go?

Sorry, I've tried 1px, 256px, png24, png8, gif and putting the img folder and/or file in every conceivable place and I'm having no luck. Maybe you'll see something in these screenshots. Thanks for any help.

(PS. I've also tried an image with color to see if I can notice any actual change, so that's why the blank.png file looks red in the Finder thumbnail. Thanks again.)

Answer 1

Woohoo! Figured it out. This thread had the solution to change the CSS rather than the JS.

.olImageLoadError { 
    /* when OL encounters a 404, don't display the pink image */
    display: none !important;
}

This help article was helpful too, but I have not idea how to tell TileMill/MapBox to generate blank tiles rather than missing tiles. I'll get there someday.