embeded images can not show after purifying

[xifengfang]

"x" is added to the src data part.

For example

before purifying: <img src="data:image/png;base64,iVB<MoreBase64SringHere>" > after purifying: <img src="x-data:image/png;base64,iVB<MoreBase64SringHere>" >

"x-data:image/png" is an invalid value for image src. It turns out the images can not show at all in any browser.

Is there any workaround or quick fix for this?