Unnecessary call of canvas.remove() (which breaks IE compatibility)

[lutzhelm]

The call of canvas.remove() in pdfDoc.prototype.reencodeImg breaks the Internet Explorer compatibility - element.remove() is not supported.

I think that it is not even necessary to call it at this point because the element has not been appended anywhere yet and is only held by a local variable, so it should be taken care of by any browser garbage collection mechanism. The Spec states that remove() doesn't even do anything if the calling element has no parent:
https://dom.spec.whatwg.org/#dom-childnode-remove

If you want to be on the save side, you can still use the following workaround:

if (canvas.parentNode != null) {
  canvas.parentNode.removeChild(canvas);
}

But I'm sure it will never be called.