Material-ui menu item link has blue mark around it - reactjs

Question

When using the simple menu from the react material ui components with link from react router dom it leaves these two blue lines on the first link even though all the links are the same. .
The weird thing is that as soon as you click out of it the blue lines will go away. It happens only on the first link.
I have already tried to change the link to a simple anchor tag instead of the react link. That didn't work. I also tried to style the link with css and with inline styles and that didn't work
This is everything inside of the return of the menu
<div>
<Button
aria-owns={anchorEl ? 'simple-menu' : undefined}
aria-haspopup="true"
onClick={this.handleClick}
>
Open Menu
</Button>
<Menu
id="simple-menu"
anchorEl={anchorEl}
open={Boolean(anchorEl)}
onClose={this.handleClose}
>
<Link to="/"><MenuItem onClick={this.handleClose}>Home</MenuItem></Link>
<Link to="/profile"><MenuItem onClick={this.handleClose}>Profile</MenuItem></Link>
<Link to="/customize"><MenuItem onClick={this.handleClose}>Customize</MenuItem></Link>
<Link to="/logout"><MenuItem onClick={this.handleClose}>Logout</MenuItem></Link>
</Menu>
</div>
I an just wondering if there is a way to remove the two blue lines.

Answer 1

Then. I'll write in the answers
try this :
a, a:hover, a:focus { outline: none; }

Answer 2

To solve this issue Gakeko Betsi suggested to edit the css for the a element with this line a, a:hover, a:focus { outline: none; }

Answer 3

Gakeko Betsi's answer is correct, however, it is worth noting that the outline has value especially in the case of accessibility. If you do remove it via CSS make sure you provide some styling that is obvious.
Another thing to remember is that accessibility is not just something for those that have disabilities, but also for your sites' power users or people that aren't using the mouse as their main mode of navigation.
The link below goes into great depth and is a very worthwhile read - https://www.deque.com/blog/give-site-focus-tips-designing-usable-focus-indicators/