Revert "Issue #2836381 by phenaproxima, Wim Leers: Seven's entity-add-list template omits link attributes"

This reverts commit f5c79614.

(cherry picked from commit f01ac2d4)

(cherry picked from commit 892272e7)

Issue #2392729 by AlviMurtaza, Sumit kumar, Manjit.Singh, simply021, skippednote, studiozut, Vidushi Mehta, vipulaSD, vova_ob, deepakkumar14, Truptti, Maninders, vsawant, meeli, Cottser, jeffrey.vargas, lamaxi, LewisNyman, emma.maria: Optimize Seven's select boxes for small screens

(cherry picked from commit b184ba67)

Issue #2765957 by chanchal2002, Manjit.Singh, brahmjeet789, kostyashupenko, AaronChristian: Core installation page content overflows its background (CSS bug)

Issue #2667242 by Anul, felribeiro, eojthebrave, pranavbabbar: Use consistent terminology when referencing administration themes in the UI (not "admin theme")

Issue #2090937 by darketaine, thpoul, Wim Leers, ironkiat, kostyashupenko, himanshugautam, Cottser, davidhernandez, Reinmar, Bojhan, tic2000, LewisNyman, emma.maria: Seven theme: style CKEditor-native dialogs to match Drupal-native dialogs

Issue #2546248 by scythian, XaviP, darrenwh, mikebell_, ingaro, urbanlegend, jhodgdon, davidhernandez, andypost, joelpittet, emma.maria, cdykstra, Cottser, LewisNyman, joachim: Use consistent style to mention HTML tags in code comments

Issue #2714375 by kiamlaluno, malavya: hook_form_alter() implementations are still commented with a reference to a form builder that doesn't exist anymore

Issue #2489660 by katzilla, lucur, AlviMurtaza, swati_qa, ijf8090, dawehner, Cottser, ayang: Views UI text overlap in older versions of Firefox

Issue #2675522 by HOG, kostyashupenko, gvso, dawehner, pradeep22saini: Styling for Views UI rearrange filters

Issue #2407955 by dernetzjaeger, darketaine, stefan.r, ChuChuNaKu, ironkiat, LewisNyman, Cottser, wellme, mgifford, emma.maria: Clean up unused images in the Seven theme

Issue #2666792 by bojanz, dawehner, edysmp, heddn: Provide a route provider for add-page of entities

Issue #2575533 by leolando.tan, AlviMurtaza, LewisNyman, j2r, joaogarin: Add warning message to Seven and Bartik that they can change in the future

Issue #2566855 by HOG, andypost, irina.pusko: Load tour CSS in the Seven theme only when the module enabled

Issue #2528420 by cane989, andrewmacpherson, malavya, mgifford, Shabbir, Denchev, Cottser: Two H1's in Installation Process

Issue #2489450 by LewisNyman, marieke_h, kfitz, jcnventura, jibla, Bojhan, manauwarsheikh, matthodgson: Remove unnecessary focused/hover effects on details and vertical tabs

Issue #2587685 by Antti J. Salminen, lauriii, jaakko, AjitS, Sagar Ramgade, rang501: Remove references to non existing preprocess functions

Issue #2548195 by nod_, JohnAlbin, madhavvyas, sriharsha.uppuluri: Only use single quotes in JavaScript and update .eslintrc

Issue #2485425 by MathieuSpil, iro, saki007ster, Wim Leers, Manjit.Singh, wiifm, kostask, Studiographene, alvar0hurtad0, LewisNyman: Clean up editor CSS inline with our CSS standards

Issue #2580255 by Wim Leers: Remove (classy|seven)_library_info_alter() in favor of libraries-extend

Issue #2550925 by PrineShazar, maijs, LewisNyman, opdavies, justAChris: Header style in seven theme with drupal set message

Issue #2557367 by davidhernandez, joelpittet, madhavvyas, alexpott, nikkyR, Studiographene, emma.maria, xjm: Fix inline list CSS

Issue #2568099 by Wim Leers, mdrummond, mortendk: Follow-up for #2407739: Remove the js-quickedit-main-content class that was added in favor of relying on <main>

Issue #2487025 by shellshocked59, harings_rob, rteijeiro, subhojit777, vijaycs85, ashutoshsngh, aburrows, swetashahi, mradcliffe, Wim Leers, lauriii, LewisNyman, Bojhan, DeeLay, B_man, davidhernandez, lizzjoy, lweinmeister, wizonesolutions, arh1, GenerUmali, tstoeckler: Remove contextual links in Seven

Issue #478994 by valthebald, sushantpaste, LewisNyman, InternetDevels, Xano, lucastockmann, alansaviolobo, mgifford, emmajane: Please state the version you are installing

Issue #2451411 by almaudoh, Shamsher_Alam, lauriii, borisson_, cilefen, davidhernandez, Cottser, Wim Leers, joelpittet: Add libraries-override to themes' *.info.yml

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 #2476947 by mdrummond, Wim Leers, davidhernandez, lauriii, joelpittet, andypost, Cottser, JeroenT, Manuel Garcia, rpayanm: Convert "title" page element into a block

Issue #2405057 by nlisgo, Manjit.Singh, ctraltdel, madhavvyas, avitslv, LewisNyman, emma.maria, joelpittet, dernetzjaeger, wmortada, karolus, cilefen, Noe_, davidhernandez, idebr: Replace arrow-asc and arrow-desc images with Libricons and implement using CSS

Issue #2566597 by Cottser, LewisNyman, mdrummond, pjbaert, jaxxed, ManuelGarcia, emma.maria, maked1sky, davidhernandez: [Mega patch] Move system *.theme.css files to Classy

This reverts commit 7cabfeee.

This reverts commit fb07e7bb.