Mostly stolen from elsewhere:
! Stop sites from prompting to sign into Google account
||accounts.google.com/gsi/*$xhr,script,3p
! Stop annoying reels from littering friend feeds
www.facebook.com##[aria-label="reel"]:upward(2)
youtube.com##.ytp-ce-element
youtube.com##.ytp-ce-element-show
youtube.com##+js(set, yt.config_.openPopupConfig.supportedPopups.adBlockMessageViewModel, false)
youtube.com##+js(set, Object.prototype.adBlocksFound, 0)
youtube.com##+js(set, ytplayer.config.args.raw_player_response.adPlacements, [])
youtube.com##+js(set, Object.prototype.hasAllowedInstreamAd, true)
! Don't use the obnoxious new bold font for titles, use the old font instead
www.youtube.com###title h1 yt-formatted-string:style(font-family: Arial, sans-serif !important; font-weight: 400 !important;)
www.youtube.com##h3.ytd-playlist-panel-renderer .title .yt-formatted-string:style(font-family: Arial, sans-serif !important; font-weight: 400 !important;)
! Remove branding bugs in the bottom corner
www.youtube.com##div.iv-branding
www.youtube.com##.annotation.annotation-type-custom.iv-branding
! Disable live video previews on hover
www.youtube.com##+js(aeld, /^(?:mousemove|pointermove|pointerenter)$/, buttons)
! Remove "Scroll for details"
www.youtube.com##.ytp-button.ytp-fullerscreen-edu-button
! Remove "This video contains paid content" warning
www.youtube.com##.ytp-paid-content-overlay
! Remove badges
www.youtube.com##.ytd-compact-video-renderer.style-scope.badges
www.youtube.com##ytd-badge-supported-renderer.ytd-video-primary-info-renderer
! Remove badges in lists, expand video title to fill that space again
www.youtube.com##.ytd-badge-supported-renderer.style-scope.badge-style-type-verified.badge
www.youtube.com###menu > .ytd-compact-video-renderer.style-scope
www.youtube.com##.ytd-compact-video-renderer.style-scope.metadata:style(padding-right:0!important)
! Remove chat
www.youtube.com###chat
! Remove sidebar
www.youtube.com##ytd-mini-guide-renderer.ytd-app.style-scope
www.youtube.com##ytd-app[mini-guide-visible] ytd-page-manager.ytd-app:style(margin-left:0px!important)
! Remove the shadow over the top of videos
www.youtube.com##div.ytp-gradient-top
www.youtube.com##.ytp-chrome-top
! Reduce opacity of the shadow over the bottom of videos
www.youtube.com##div.ytp-gradient-bottom:style(opacity: 55% !important)
! Reduce opacity of video length labels
www.youtube.com##ytd-thumbnail-overlay-time-status-renderer.ytd-thumbnail.style-scope:style(opacity:75% !important)
! Remove Next button. I only ever hit this accidentally, losing my place
! and my playback buffer >:-[
www.youtube.com##.ytp-left-controls > .ytp-button.ytp-next-button
! Remove Miniplayer button
www.youtube.com##.ytp-button.ytp-miniplayer-button
! Force YouTube to display the complete copyright information in the description
www.youtube.com###expanded-metadata:style(display:block !important)
! Don't load the preview image before the video loads (saves some bandwidth)
||i.ytimg.com/vi_webp/*/maxresdefault.webp
||i.ytimg.com/vi/*/maxresdefault.jpg
! Remove interactions (eg if you never login to YouTube)
www.youtube.com###like-button
www.youtube.com###dislike-button
www.youtube.com###sponsor-button
www.youtube.com###hover-overlays
www.youtube.com###subscribe-button
www.youtube.com###flexible-item-buttons
www.youtube.com###button-shape
www.youtube.com###reply-button-end
! Remove sidebar items that are only applicable to logged-in users
www.youtube.com##ytd-guide-section-renderer.ytd-guide-renderer.style-scope:nth-of-type(1)
www.youtube.com##ytd-guide-section-renderer.ytd-guide-renderer.style-scope:nth-of-type(2)
! Remove "Watch Later" and "Add to Queue"
www.youtube.com###hover-overlays
! Remove the "skeleton" shown before the page loads
www.youtube.com##.skeleton
www.youtube.com###info-skeleton
www.youtube.com###meta-skeleton
www.youtube.com###owner-name
www.youtube.com##.skeleton-bg-color
www.youtube.com###home-page-skeleton
www.youtube.com###masthead-skeleton-icons
||www.youtube.com/s/desktop/*/cssbin/www-main-desktop-watch-page-skeleton.css
||www.youtube.com/s/desktop/*/cssbin/www-main-desktop-player-skeleton.css
! Remove the live previews on the scrubber bar (saves some bandwidth, but
! not worth it IMO)
||i.ytimg.com/sb/*
www.youtube.com##div.ytp-tooltip-bg
www.youtube.com##div.ytp-tooltip-image
www.youtube.com##div.ytp-tooltip:style(border-radius:0px;!important)*