AJAX response processing hangs when header contains link with non-standard rel attribute

[whowrotethiscode]

Hello,

When a Panel contains the following code and is rendered via AJAX
then the AJAX response processing in the client browser will hang indefinitely:

    @Override
    public void renderHead(IHeaderResponse response) {
        super.renderHead(response);

        response.render(StringHeaderItem.forString(
                "<link rel=\"stylesheet/less\" type=\"text/css\" href=\"demo.less\" media=\"all\"/>"));
    }

It seems the non-standard rel="stylesheet/less"
causes wicket-ajax-jquery.js to wait for an onload event which never happens.

The above code worked OK in Wicket version 8
but it now hangs after upgrading to Wicket version 10.

Please see this minimal reproducible example: ajax-hang-demo.zip

Thanks to the Wicket team.

Environment

• Hangs in Wicket version 10.9.0
• Worked OK in Wicket 8.18.0
• Reproducible in all modern browsers

[reiern70]

Could you please create a Jira ISSUE for this?