Issue #1493324 by tim.plunkett, dmsmidt, mgifford, bleen18, davidhernandez, crasx, mparker17, stefan.r, YesCT, joelpittet, tstoeckler, larowlan, vijaycs85, swentel, rpayanm, Bojhan, LewisNyman, emma.maria, BarisW, njbarrett, rteijeiro, nod_, sun, joshtaylor, mrjmd, webchick, marcvangend, kattekrab, SKAUGHT, bowersox, andrewmacpherson, Manjit.Singh, RavindraSingh, Wim Leers, BLadwin, aspilicious, mortendk, mausolos, jessebeach, Gábor Hojtsy, anandps, falcon03, franz, andypost, rooby, rootwork, Cottser, Xano: Inline form errors for accessibility and UX

Issue #2307647 by Wim Leers | anandps: [Follow-up] Allow manual override of required image alt text in the Text Editor image dialog when appropriate.

Issue #2125621 by davidhernandez, mgifford, jessebeach, mparker17, anandps: Fixed Contrast between title/slogan and header is too low.

Revert "Issue #2125621 by anandps, mgifford, davidhernandez, jessebeach, mparker17: Fixed drupala11y.org finds two new color contrast issues."

Needs more discussion/review, given strong visual impact.

This reverts commit cdf25d79.

Issue #2125621 by anandps, mgifford, davidhernandez, jessebeach, mparker17: Fixed drupala11y.org finds two new color contrast issues.