Release 4.9.0

Features

• adding the wcag131 tag to the aria-hidden-body rule (#4349) (dd4c3c3), closes #4315
• checks: deprecate aria-busy check (#4356) (be0b555), closes #4347 #4340
• color: add color channel values and luminosity, saturation, clip functions (#4366) (9e70199), closes /github.com/dequelabs/axe-core/pull/4365/files#r1517706612
• i18n: add Greek Translations (#3836) (3ea9a48)
• i18n: Add Italian translation (#4344) (de1baa9)
• i18n: Add Simplified Chinese translation (#4379) (bda7c8d)
• i18n: Add Taiwanese Mandarin translation (#4299) (c5e11de)

Bug Fixes

• Add LICENSE-3RD-PARTY.txt file (#4304) (daa0fe6)
• add Object.values polyfill for node <=6 (#4274) (5eb867b)
• aria-required-children: avoid confusing aria-busy message in failures (#4347) (591607d), closes #fail13 #4340
• avoid reading element-specific node properties of non-element node types (#4317) (b853b18), closes #4316 #4316
• color-contrast: handle text that is outside overflow: hidden ancestor (#4357) (bdb7300), closes #4253
• color-contrast: support color blend modes hue, saturation, color, luminosity (#4365) (7ae4761)
• d.ts: RawNodesResult issues (#4229) (d660518)
• d.ts: RunOptions.reporter can be any string (#4218) (e53f5c5)
• i18n: update Italian translations (#4377) (4d65d4b)
• listitem: clarify roleNotValid message (#4374) (0f8a9af)
• scrollable-region-focusable: missing wcag213 tag (#4201) (0080a72)
• target-size: always pass 10x targets (avoid perf bottleneck) (#4376) (be327c4)
• target-size: do not crash for nodes with many overlapping widgets (#4373) (1dbea83), closes #4359 #4359 #4360
• utils/get-selector: ignore 'xmlns' attribute when generating a selector (#4303) (938b411)