fredj/openlayers — comment on commit 2ba09f7b004926aebdfc25fa95a1b051e6a59a34
File:  line 0
By ahocevar:

As far as I remember, I had this at some point during the development of the new tile code, but removed it again because setting img.src seems to be CPU intensive on some browsers, and it fires load or error events (depending on the browser). Maybe it would work to set img.src to blankImageUrl in onImageError instead?