There are many default usability styles designed by the browser.
Sometimes it is best to leave it alone because it covers a lot of area that you might not be able to cover if you nitpick it.
Now if the color of the outline clashes with your branding like “blue is really banned from your UI” then change it.
Or if the outline color is the same as the background color, it won’t be seen, of course, so change it.
It’s important to note that styles whose main purpose is usability must be left alone especially if your purpose is to simply comply with color schemes.