Lightning button icon without border

Question

Is it possible to remove the border on a lightning button icon when it clicked?

<lightning:buttonIcon iconName="utility:dislike" variant="bare" onclick="{!c.downVote}"  size="medium"" 
<lightning:buttonIcon iconName="utility:like" variant="bare" onclick="{!c.upVote}"  size="medium" " />

Answer 1

As sfdcfox already said That border is there to indicate active focus.....

but if you still want to remove it assign a class to button icon like this

<lightning:buttonIcon iconName="utility:like" variant="bare"  alternativeText="Settings" size="medium" class="test" />

then use that class to target during focus css

.THIS .test:focus{
   box-shadow:none;

}

if button icon is first element then

.THIS.test:focus{
   box-shadow:none;

}