Add failover setting step controls

test/web/style-source.js

@@ -481,7 +481,7 @@ const OBSERVED_PROPERTIES = new Set(`
 --client-accent --client-accent-soft --client-bg --client-border --client-control
 --client-delete-strike-y --client-device-chart-height --client-device-copy-color --client-rule-drag-y
 --client-muted --client-panel --client-power-top --client-text --client-work-height
---harbor-connect --harbor-gateway --harbor-word -webkit-backdrop-filter
+--harbor-connect --harbor-gateway --harbor-word -webkit-appearance -webkit-backdrop-filter
 -webkit-text-fill-color align-content align-items align-self animation
 animation-duration animation-name animation-timing-function appearance backdrop-filter
 background background-color border border-bottom border-bottom-color border-collapse
@@ -520,7 +520,8 @@ const PROPERTY_FAMILIES = new Map([
 const SUPPORTED_SELECTOR_NODES = new Set(['attribute', 'class', 'combinator', 'id', 'pseudo', 'selector', 'tag', 'universal']);
 const SUPPORTED_COMBINATORS = new Set([' ', '+', '>']);
 const SUPPORTED_PSEUDOS = new Set([
-  ':-webkit-autofill', '::-webkit-scrollbar', '::after', '::before', '::marker', '::placeholder',
+  ':-webkit-autofill', '::-webkit-inner-spin-button', '::-webkit-outer-spin-button', '::-webkit-scrollbar',
+  '::after', '::before', '::marker', '::placeholder',
   '::view-transition-group', '::view-transition-new', '::view-transition-old', ':active', ':disabled',
   ':first-child', ':focus', ':focus-visible', ':focus-within', ':has', ':hover', ':last-child', ':not',
   ':nth-child', ':root',