Steps to replicate the issue (include links if applicable):
- Visit https://www.mediawiki.org/wiki/MediaWiki, toggle between desktop and mobile view
What happens?:
The image doesn't have a border on mobile view:
What should have happened instead?:
The image has a border as in the desktop view.
Software version (on Special:Version page; skip for WMF-hosted wikis like Wikipedia):
Other information (browser name/version, screenshots, etc.):
MinervaNeue is still referencing the old class (thumbborder) used in the legacy media DOM: resources/skins.minerva.styles/content/thumbnails.less#55
Core styles for the border: resources/src/mediawiki.skinning/content.media-screen.less#9

