wpt / css / css-masking / animations / mask-border-outset-interpolation.html

Status: FAIL | Duration: 353ms | Subtests: 0/168 | Open test on wpt.live | wpt.fyi

TestTest SourceSubtests (0/168)

Data from commit:
a50cb89 wpt: run reference-named files which are themselves tests (#836) (2026-09-03)

SubtestStatusMessage
CSS Transitions: property <mask-border-outset> from neutral to [2px] at (-0.3) should be [0.7px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from neutral to [2px] at (0) should be [1px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from neutral to [2px] at (0.3) should be [1.3px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from neutral to [2px] at (0.6) should be [1.6px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from neutral to [2px] at (1) should be [2px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from neutral to [2px] at (1.5) should be [2.5px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from neutral to [2px] at (-0.3) should be [0.7px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from neutral to [2px] at (0) should be [1px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from neutral to [2px] at (0.3) should be [1.3px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from neutral to [2px] at (0.6) should be [1.6px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from neutral to [2px] at (1) should be [2px]FAILassert_true: 'to' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from neutral to [2px] at (1.5) should be [2.5px]FAILassert_true: 'to' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from neutral to [2px] at (-0.3) should be [0.7px]FAILassert_true: 'to' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from neutral to [2px] at (0) should be [1px]FAILassert_true: 'to' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from neutral to [2px] at (0.3) should be [1.3px]FAILassert_true: 'to' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from neutral to [2px] at (0.6) should be [1.6px]FAILassert_true: 'to' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from neutral to [2px] at (1) should be [2px]FAILassert_true: 'to' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from neutral to [2px] at (1.5) should be [2.5px]FAILassert_true: 'to' value should be supported expected true got false
Web Animations: property <mask-border-outset> from neutral to [2px] at (-0.3) should be [0.7px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from neutral to [2px] at (0) should be [1px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from neutral to [2px] at (0.3) should be [1.3px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from neutral to [2px] at (0.6) should be [1.6px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from neutral to [2px] at (1) should be [2px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from neutral to [2px] at (1.5) should be [2.5px]FAILassert_true: Web Animations should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [initial] to [2] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [initial] to [2] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [initial] to [2] at (0.3) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [initial] to [2] at (0.6) should be [1.2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [initial] to [2] at (1) should be [2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [initial] to [2] at (1.5) should be [3]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [initial] to [2] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [initial] to [2] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [initial] to [2] at (0.3) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [initial] to [2] at (0.6) should be [1.2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [initial] to [2] at (1) should be [2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [initial] to [2] at (1.5) should be [3]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [initial] to [2] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [initial] to [2] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [initial] to [2] at (0.3) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [initial] to [2] at (0.6) should be [1.2]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [initial] to [2] at (1) should be [2]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [initial] to [2] at (1.5) should be [3]FAILassert_true: 'from' value should be supported expected true got false
Web Animations: property <mask-border-outset> from [initial] to [2] at (-0.3) should be [0]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [initial] to [2] at (0) should be [0]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [initial] to [2] at (0.3) should be [0.6]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [initial] to [2] at (0.6) should be [1.2]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [initial] to [2] at (1) should be [2]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [initial] to [2] at (1.5) should be [3]FAILassert_true: Web Animations should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [inherit] to [2px] at (-0.3) should be [12.4px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [inherit] to [2px] at (0) should be [10px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [inherit] to [2px] at (0.3) should be [7.6px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [inherit] to [2px] at (0.6) should be [5.2px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [inherit] to [2px] at (1) should be [2px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [inherit] to [2px] at (1.5) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [inherit] to [2px] at (-0.3) should be [12.4px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [inherit] to [2px] at (0) should be [10px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [inherit] to [2px] at (0.3) should be [7.6px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [inherit] to [2px] at (0.6) should be [5.2px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [inherit] to [2px] at (1) should be [2px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [inherit] to [2px] at (1.5) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [inherit] to [2px] at (-0.3) should be [12.4px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [inherit] to [2px] at (0) should be [10px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [inherit] to [2px] at (0.3) should be [7.6px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [inherit] to [2px] at (0.6) should be [5.2px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [inherit] to [2px] at (1) should be [2px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [inherit] to [2px] at (1.5) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
Web Animations: property <mask-border-outset> from [inherit] to [2px] at (-0.3) should be [12.4px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [inherit] to [2px] at (0) should be [10px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [inherit] to [2px] at (0.3) should be [7.6px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [inherit] to [2px] at (0.6) should be [5.2px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [inherit] to [2px] at (1) should be [2px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [inherit] to [2px] at (1.5) should be [0px]FAILassert_true: Web Animations should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [unset] to [2] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [unset] to [2] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [unset] to [2] at (0.3) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [unset] to [2] at (0.6) should be [1.2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [unset] to [2] at (1) should be [2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [unset] to [2] at (1.5) should be [3]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [unset] to [2] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [unset] to [2] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [unset] to [2] at (0.3) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [unset] to [2] at (0.6) should be [1.2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [unset] to [2] at (1) should be [2]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [unset] to [2] at (1.5) should be [3]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [unset] to [2] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [unset] to [2] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [unset] to [2] at (0.3) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [unset] to [2] at (0.6) should be [1.2]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [unset] to [2] at (1) should be [2]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [unset] to [2] at (1.5) should be [3]FAILassert_true: 'from' value should be supported expected true got false
Web Animations: property <mask-border-outset> from [unset] to [2] at (-0.3) should be [0]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [unset] to [2] at (0) should be [0]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [unset] to [2] at (0.3) should be [0.6]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [unset] to [2] at (0.6) should be [1.2]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [unset] to [2] at (1) should be [2]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [unset] to [2] at (1.5) should be [3]FAILassert_true: Web Animations should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0px] to [5px] at (-0.3) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0px] to [5px] at (0) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0px] to [5px] at (0.3) should be [1.5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0px] to [5px] at (0.6) should be [3px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0px] to [5px] at (1) should be [5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0px] to [5px] at (1.5) should be [7.5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0px] to [5px] at (-0.3) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0px] to [5px] at (0) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0px] to [5px] at (0.3) should be [1.5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0px] to [5px] at (0.6) should be [3px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0px] to [5px] at (1) should be [5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0px] to [5px] at (1.5) should be [7.5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0px] to [5px] at (-0.3) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0px] to [5px] at (0) should be [0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0px] to [5px] at (0.3) should be [1.5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0px] to [5px] at (0.6) should be [3px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0px] to [5px] at (1) should be [5px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0px] to [5px] at (1.5) should be [7.5px]FAILassert_true: 'from' value should be supported expected true got false
Web Animations: property <mask-border-outset> from [0px] to [5px] at (-0.3) should be [0px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0px] to [5px] at (0) should be [0px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0px] to [5px] at (0.3) should be [1.5px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0px] to [5px] at (0.6) should be [3px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0px] to [5px] at (1) should be [5px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0px] to [5px] at (1.5) should be [7.5px]FAILassert_true: Web Animations should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0] to [1] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0] to [1] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0] to [1] at (0.3) should be [0.3]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0] to [1] at (0.6) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0] to [1] at (1) should be [1]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [0] to [1] at (1.5) should be [1.5]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0] to [1] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0] to [1] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0] to [1] at (0.3) should be [0.3]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0] to [1] at (0.6) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0] to [1] at (1) should be [1]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [0] to [1] at (1.5) should be [1.5]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0] to [1] at (-0.3) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0] to [1] at (0) should be [0]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0] to [1] at (0.3) should be [0.3]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0] to [1] at (0.6) should be [0.6]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0] to [1] at (1) should be [1]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [0] to [1] at (1.5) should be [1.5]FAILassert_true: 'from' value should be supported expected true got false
Web Animations: property <mask-border-outset> from [0] to [1] at (-0.3) should be [0]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0] to [1] at (0) should be [0]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0] to [1] at (0.3) should be [0.3]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0] to [1] at (0.6) should be [0.6]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0] to [1] at (1) should be [1]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [0] to [1] at (1.5) should be [1.5]FAILassert_true: Web Animations should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (-0.3) should be [0 0 0px 0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0) should be [1 2 3px 4px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.3) should be [31 32 33px 34px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.6) should be [61 62 63px 64px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1) should be [101 102 103px 104px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1.5) should be [151 152 153px 154px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (-0.3) should be [0 0 0px 0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0) should be [1 2 3px 4px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.3) should be [31 32 33px 34px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.6) should be [61 62 63px 64px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1) should be [101 102 103px 104px]FAILassert_true: 'from' value should be supported expected true got false
CSS Transitions with transition: all: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1.5) should be [151 152 153px 154px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (-0.3) should be [0 0 0px 0px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0) should be [1 2 3px 4px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.3) should be [31 32 33px 34px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.6) should be [61 62 63px 64px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1) should be [101 102 103px 104px]FAILassert_true: 'from' value should be supported expected true got false
CSS Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1.5) should be [151 152 153px 154px]FAILassert_true: 'from' value should be supported expected true got false
Web Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (-0.3) should be [0 0 0px 0px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0) should be [1 2 3px 4px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.3) should be [31 32 33px 34px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (0.6) should be [61 62 63px 64px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1) should be [101 102 103px 104px]FAILassert_true: Web Animations should be supported expected true got false
Web Animations: property <mask-border-outset> from [1 2 3px 4px] to [101 102 103px 104px] at (1.5) should be [151 152 153px 154px]FAILassert_true: Web Animations should be supported expected true got false

/css/css-masking/animations/mask-border-outset-interpolation.html

<!DOCTYPE html>
<meta charset="UTF-8">
<title>mask-border-outset interpolation</title>
<link rel="help" href="https://drafts.fxtf.org/css-masking/#propdef-mask-border-outset">
<link rel="author" title="Tim Nguyen" href="https://github.com/nt1m">
<meta name="assert" content="mask-border-outset supports animation by computed value">

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/css/support/interpolation-testcommon.js"></script>

<style>
.parent {
  mask-border-outset: 10px;
}
.target {
  width: 50px;
  height: 50px;
  background-color: black;
  display: inline-block;
  border: 25px;
  margin-right: 50px;
  mask-border-slice: 30%;
  background-clip: content-box;
  mask-border-source: linear-gradient(45deg, pink, blue, white, black, green);
  mask-border-outset: 1px;
}
.expected {
  background-color: green;
}
</style>

<body></body>

<script>
test_interpolation({
  property: 'mask-border-outset',
  from: neutralKeyframe,
  to: '2px',
}, [
  {at: -0.3, expect: '0.7px'},
  {at: 0, expect: '1px'},
  {at: 0.3, expect: '1.3px'},
  {at: 0.6, expect: '1.6px'},
  {at: 1, expect: '2px'},
  {at: 1.5, expect: '2.5px'},
]);

test_interpolation({
  property: 'mask-border-outset',
  from: 'initial',
  to: '2',
}, [
  {at: -0.3, expect: '0'}, // Non-negative
  {at: 0, expect: '0'},
  {at: 0.3, expect: '0.6'},
  {at: 0.6, expect: '1.2'},
  {at: 1, expect: '2'},
  {at: 1.5, expect: '3'},
]);

test_interpolation({
  property: 'mask-border-outset',
  from: 'inherit',
  to: '2px',
}, [
  {at: -0.3, expect: '12.4px'},
  {at: 0, expect: '10px'},
  {at: 0.3, expect: '7.6px'},
  {at: 0.6, expect: '5.2px'},
  {at: 1, expect: '2px'},
  {at: 1.5, expect: '0px'},
]);

test_interpolation({
  property: 'mask-border-outset',
  from: 'unset',
  to: '2',
}, [
  {at: -0.3, expect: '0'}, // Non-negative
  {at: 0, expect: '0'},
  {at: 0.3, expect: '0.6'},
  {at: 0.6, expect: '1.2'},
  {at: 1, expect: '2'},
  {at: 1.5, expect: '3'},
]);

test_interpolation({
  property: 'mask-border-outset',
  from: '0px',
  to: '5px',
}, [
  {at: -0.3, expect: '0px'}, // Non-negative
  {at: 0, expect: '0px'},
  {at: 0.3, expect: '1.5px'},
  {at: 0.6, expect: '3px'},
  {at: 1, expect: '5px'},
  {at: 1.5, expect: '7.5px'},
]);

test_interpolation({
  property: 'mask-border-outset',
  from: '0',
  to: '1',
}, [
  {at: -0.3, expect: '0'}, // Non-negative
  {at: 0, expect: '0'},
  {at: 0.3, expect: '0.3'},
  {at: 0.6, expect: '0.6'},
  {at: 1, expect: '1'},
  {at: 1.5, expect: '1.5'},
]);

test_interpolation({
  property: 'mask-border-outset',
  from: '1 2 3px 4px',
  to: '101 102 103px 104px',
}, [
  {at: -0.3, expect: '0 0 0px 0px'}, // Non-negative
  {at: 0, expect: '1 2 3px 4px'},
  {at: 0.3, expect: '31 32 33px 34px'},
  {at: 0.6, expect: '61 62 63px 64px'},
  {at: 1, expect: '101 102 103px 104px'},
  {at: 1.5, expect: '151 152 153px 154px'},
]);
</script>