Usually the bar is generated exactly by the code.
I recreated it using my Riley template.
I put this in a module in the "Code" editor:
<blockquote>
<p>Your list entry goes here! fasfdsfsd sdfsdfsf sdf sdf sdfsdfdsf sdfsdf sdfsdf sdfsdf</p>
</blockquote>
If I then display the module on the website, the vertical bar appears. You can then change the color with CSS
see also my picture