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YouTube - Square Corners for Thumbnails and Avatars

Makes YouTube thumbnail image corners square again

/* ==UserStyle==
@name           YouTube - Square Corners for Thumbnails and Avatars
@description    Makes YouTube thumbnail image corners square again
@namespace      lednerg
@version        23.2.5.18
@author         lednerg
@license        CC-BY-NC-SA-4.0
@preprocessor   stylus
@var    checkbox    avatars    "Square avatars?"    1
==/UserStyle== */
@-moz-document domain("youtube.com") {

    #thumbnail,
    #tile-container,
    ytd-post-renderer,
    ytd-post-renderer:before,
    ytd-thumbnail:before,
    .ytd-hero-playlist-thumbnail-renderer,
    .video-stream,
    .html5-video-player,
    .ytp-miniplayer-scrim,
    ytd-channel-video-player-renderer[rounded],
    #player.ytd-channel-video-player-renderer {
        border-radius: 0 !important;
    }
    if avatars {
        #author-photo,
        #avatar,
        #author-thumbnail yt-img-shadow,
        .ytd-guide-entry-renderer,
        #channel yt-img-shadow {
            border-radius: 0 !important;
        }
    }
}