HTML images contain no text applies to rendered image resource. These, in turn, include "resource (…) that has been specified in the list of image sources of an embedded image." And embedded image lists img, <input type="image">, background-image, …
The problem is that image sources is only defined in HTML for img elements (and link).
So, an <input type="image"> has no "image sources", and therefore no "resource specified in its (non-existent) image sources", and therefore no "rendered image resource" and is technically inapplicable.
(the meaning is fairly obvious, but should be made technically correct)
HTML images contain no text applies to rendered image resource. These, in turn, include "resource (…) that has been specified in the list of image sources of an embedded image." And embedded image lists
img,<input type="image">,background-image, …The problem is that image sources is only defined in HTML for
imgelements (andlink).So, an
<input type="image">has no "image sources", and therefore no "resource specified in its (non-existent) image sources", and therefore no "rendered image resource" and is technically inapplicable.(the meaning is fairly obvious, but should be made technically correct)