Unsupported <object> elements turn into red question marks with HTMLEditorKit

A DESCRIPTION OF THE PROBLEM :
When viewing an HTML document with HTMLEditorKit, if the page contains an <object> element with an unsupported classid, the element is turned into two red question marks "??". This is annoying because it prevents the usage of a fallback mechanism like this:

<object data="duke.svg" type="image/svg+xml">
  <img src="duke.png">
</object>

In this case HTMLEditorKit properly renders the fallback image, but the question marks are still displayed.

It's possible to work around this issue by specifying the class name of a Swing component in the classid attribute:

<object data="duke.svg" type="image/svg+xml" classid="javax.swing.JLabel">
  <img src="duke.png">
</object>

This removes the question marks, but now the object won't load in a standard browser supporting SVG images.

I'd suggest removing the red question marks, i.e. modify rgz getUnloadableRepresentation() method in javax.swing.text.html.ObjectView to return an empty JLabel.


FREQUENCY : always