Issue #3343212 by markconroy, andy-blum, bnjmnm, longwave, alexpott, lauriii, codexmas, harsha012, rpayanm, occupant, Mukeysh, leahtard, joelpittet: Update Core CSS to use double-colon for pseudo elements

Issue #2209063 by bnjmnm, Sam152, tarekdj, lauriii, Wim Leers, LewisNyman, quietone: Fix the flicker of the "active" icons when a high-latency user clicks on toolbar items

Issue #2866818 by harsha012, BrightBold, brahmjeet789, joelpittet: Update stylelint rule number-leading-zero to be consistent with Drupal's CSS standards

Issue #2566771 by Cottser, mortendk, jstoller, LewisNyman, mdrummond, Gints Ērglis, sqndr, Chernous_dn, Manjit.Singh, axe312, emma.maria, davidhernandez, lauriii, jaxxed, akalata: [Voltron patch] Move all remaining *.theme.css to Classy

Issue #2563955 by bruvers, sushantpaste, shwetaneelsharma, LewisNyman: Confirm Password "Passwords match" text color

Issue #2031641 by aburrows, lauriii, nlisgo, Pol, redsquid, tuutti, LewisNyman, akalata, agviu, kallehauge, _nolocation, rpayanm, saki007ster, mdrummond, RavindraSingh, brahmjeet789: Change active class to is-active

Issue #1663210 by mortendk, rootwork, idebr, vks7056, ishmael-sanchez, LewisNyman, joelpittet, Manjit.Singh, Manuel Garcia, b0unty, prajaankit, alansaviolobo, atu: Clean up css in the User module

Issue #2372023 by andybroomfield, BarisW, aspilicious, LewisNyman, Vally79, tompagabor: Description of display settings takes too much space

Issue #2368739 by Wim Leers: Fixed user_page_attachments() unnecessarily adds an individual CSS file on every page.

Issue #2318677 by bluegriff | emma.maria: Fixed Password field focus is interfering with the password indicator strength bar.

Issue #2318679 by bluegriff | emma.maria: Fixed "Password strength: Strong" wraps onto a second line.

Issue #2309137 by longwave, sqndr | LewisNyman: Remove quotes from all background-image: url() properties.

Issue #2247049 by sqndr, herom, LewisNyman: Redesign password strength indicator so it's less fragile.

Issue #2100509 by emma.maria, dcrocks, csakiistvan, Manjit.Singh: Password strength indicator for site maintenance account is aligned incorrectly on the installation screen.

Issue #1839318 by JohnAlbin, echoz: Added Replace drupal.base.css library with normalize.css for all themes.

Issue #1963886 by ry5n, jessebeach, dcrocks, Wim Leers: Use HiDPI icons in the toolbar to support scaling on different devices.

Issue #1938044 by hass, jessebeach, Dragan Eror: Fixed Prefix all toolbar classes to prevent theme clashes.

Issue #2015789 by fubhy, echoz, rteijeiro, LewisNyman, penyaskito: Remove language_css_alter() (RTL stylesheets) in favor of HTML 'dir' attribute.

Issue #1987066 by Kevin Morse, JohnAlbin, rteijeiro, echoz, ry5n: Rename files to match CSS file naming convention.