BREAKING CHANGES

section-title: The div.section-title__cta that previously contained an a which contained span.section-title__cta-text has been simplified to a.section-title__cta losing some nesting. Also removed section-title--small and other sizes since component should be responsive.
star-rating (dynamic variation) and star-rating-dynamic had the new star icon svg markup manually inserted since it does additional work to clip the star(s) when building the component(s).
spinner has 3 sizes now, small, regular, and large. Small and regular are new sizes (16px, and 24px respectively). The old regular spinner is now the large (at 30px), and the old large spinner has been removed. We also removed the background image version of the spinner code, so you need to migrate to using the icon image for spinner.
stepper has some major visual changes and simplified code. Removed information icon from stepper. Removed all transition classes.
Removed expand-button module. Should use Expandable Buttons instead (see skin docs under button)
Removed wide button styles
Removed window-notice module. This has been deprecated for a while and finally removed.
Removed multiple icon modules. All icons are either icons.svg or each icon individually.
Removed lightbox-dialog--mini styles
Removed panel dialog center title
Removed all --bubble-* variables from tooltip/infotip/tourtip

List of changes

chore: removed deprecated code (#1841)
chore(deprecations): removed expand button and window notice (#1847)
feat(snackbar-dialog): updated to match design system (#1850)
feat: updated stepper to new design (#1857)
feat(spinner): updated to evo (#1858)
feat(field description): removed left and right margins
fix(menu-button): fix multible button alignment (#1849)
fix(button): removed min-width on borderless variant (#1853)
feat: added old dot syntax to progress-stepper (#1863)
fix: added stronger selectors to disbled fake-menu-button (#1865)
feat(section-title): updated section titles to match new specs (#1867)
feat(star-icons): updated star icons and proliferated throughout various components (#1872)
fix: remove deprecated story and modify CSS selector (#1875)

Full Changelog: v14.2.1...v15.0.0