Button shadow while scrolling horizontally

You can see in the video below the buttons have something like a shadow on the outside while scrolling:

Is there a way to prevent the outer shadows?

Inspector from one Button:

I don’t think that is related to the Unity. It is just how human eyes perceive the color information that is causing this paradoxical artifact.

And I did a quick test with the code HTML/CSS below inside a browser and on scrolling it creates the same effect with these boxes too. You can copy paste this code in a file and save it as .html and view that page in browser to check the same effect happening here.

<html>
<head>
<style>
#wrapper {
  width: 200%;
}
.box {
  float: left;
  width: 100px;
  height: 100px;
  margin: 10px;
  border-radius: 25px;
  background: #000000;
}
</style>
</head>    
<body>
<div id="wrapper">
<div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div><div class = "box"></div>
</div>
</body>
</html>