White corners are displaying on active tab.

Working on this issue.

I have create a MR could you please review it. i have attached the screenshot after MR now its working fine at my end

I am using drupal version 10.6.2-dev

I noticed this change removes the focus outline entirely for the active tab. While this visually hides the white corner issue, it also removes the focus indicator altogether, which impacts keyboard navigation and accessibility.

The underlying issue seems to be the outline not respecting border-radius, which is why the corner artifacts appear. Instead of disabling focus styles, we should replace the outline with a custom focus style (e.g. using box-shadow) that matches the rounded tabs while keeping focus visible.
Also i was working on it as mentioned in the comment, Please make sure to follow drupal guidelines as you are an experienced contributor. And you have only pushed the changes but have not created a MR, so please create a MR after pushing the changes.
Thank you

@divyansh.gupta On Drupal.org, there are no policies that prevent another person from working on a bug task if it has already been assigned to someone else.
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@Ravi Kant
Using outline-offset: -1px will not resolve the issue, as it applies a border to all sides rather than addressing the specific requirement.

Thank you for reporting this and for working on a fix. I was able to reproduce the visual issue with the Material Tabs style: the active/focused tab can show white square corners around the rounded tab.

I am not comfortable merging the current approach as-is because it removes the focus outline. That does hide the visual artifact, but it also removes the visible focus indicator for keyboard users, which is an accessibility regression.

I think the fix should preserve a visible focus state while avoiding the square-corner artifact.

The current patch removes the focus outline, which resolves the visual artifact but introduces an accessibility regression because keyboard users no longer have a visible focus indicator.

Instead of removing the focus state, I recommend replacing the outline with a box-shadow based focus ring. Box-shadow respects border-radius and avoids the square corner artifact while maintaining WCAG-compliant focus visibility.

That looks way better and the artifacts are gone! Thanks @akshay kashyap for persisting.

Side note on contributing: The 'Assigned' field can be useful, but as a maintainer it's more of a pain because it inadvertently blocks other contributors from helping, more often than not people (with good intentions) assign themselves then life takes them away from it, meanwhile people are expecting something from them and holding off helping as a result. Best practice (from my prospective as a old-school contrib mentor), comment that you are intending to work on it, and that should suffice.