iframe not displayed

[kgashok]

An iframe does not get displayed. I am using Chrome. What do I have to do?
(I've enabled scripting as per https://projectinsight.net/support/kb/chrome-blocks-iframe, and it still does not load).

<h1 id="visual-quiz">Visual Quiz</h1>
<ol>
<li><a href="http://j.mp/badShape">http://j.mp/badShape</a> - what is the value returned by the method <code>calculateVolume()</code>. Is it wrong? How will you fix it?</li>
</ol>
<iframe width="800" height="500" src="http://pythontutor.com/iframe-embed.html#code=public%20class%20SomeShape%20%7B%0A%20%20%20%20private%20int%20height%3B%20%0A%20%20%20%20private%20int%20length%3B%20%0A%20%20%20%20private%20int%20depth%3B%20%0A%20%20%20%20%0A%20%20%20%20public%20SomeShape%20%28int%20height,%20int%20length,%20int%20depth%29%20%7B%0A%20%20%20%20%20%20%20height%20%3D%20height%3B%20%0A%20%20%20%20%20%20%20length%20%3D%20length%3B%0A%20%20%20%20%20%20%20depth%20%3D%20depth%3B%0A%20%20%20%20%7D%0A%20%20%20%20%0A%20%20%20%20public%20int%20calculateVolume%28%29%20%7B%20%0A%20%20%20%20%20%20return%20height%20*%20length%20*%20depth%3B%0A%20%20%20%20%7D%0A%20%20%20%20%0A%20%20%20%20%0A%20%20%20%20public%20static%20void%20main%28String%5B%5D%20args%29%20%7B%0A%20%20%20%20%20%20SomeShape%20s%20%3D%20new%20SomeShape%20%281,%202,%203%29%3B%20%0A%20%20%20%20%20%20int%20volume%20%3D%20s.calculateVolume%28%29%3B%0A%20%20%20%20%20%20System.out.println%28%22Volume%3A%20%22%20%2B%20volume%29%3B%20%0A%20%20%20%20%7D%0A%7D&amp;codeDivHeight=400&amp;codeDivWidth=350&amp;cumulative=false&amp;curInstr=0&amp;heapPrimitives=nevernest&amp;origin=opt-frontend.js&amp;py=java&amp;rawInputLstJSON=%5B%5D&amp;textReferences=false"> </iframe>
<ol start="2">
<li>
<p><a href="http://j.mp/thisScope">http://j.mp/thisScope</a>  - What is the compile error you notice in red? Please explain why.</p>
</li>
<li>
<p><a href="http://j.mp/thisFinal">http://j.mp/thisFinal</a>  - What is the compile error you notice in the red? Please explain why.</p>
</li>
</ol>
<h2 id="usage-of-java-this-keyword">Usage of java this keyword</h2>
<p><a href="http://j.mp/thisJavaPoint">http://j.mp/thisJavaPoint</a></p>
<p>Here is given the 6 usage of java this keyword.</p>
<ol>
<li><code>this</code> can be used to refer current class instance variable.</li>
<li><code>this</code> can be used to invoke current class method (implicitly)</li>
<li><code>this()</code> can be used to invoke current class constructor.</li>
<li><code>this</code> can be passed as an argument in the method call.</li>
<li><code>this</code> can be passed as argument in the constructor call.</li>
<li><code>this</code> can be used to return the current class instance from the method.</li>
</ol>

[disklosr]

Had this same issue yesterday. I suggest you check console output and see what error you're getting but I think (as you mentioned in your link) it has to do with the fact that you can't load an unsafe content (http) inside a safe one (https). Now you might try to load safe content inside safe content but that might also not work because some sites simply don't allow it (try google.com)

[kgashok]

I changed src="http://pythontutor.com... to src="https://pythontutor.com

There was no error in the console output. However, the link did not load up either; is it because pythontutor.com is unable to load in safe mode?