maskBorderSource
This feature is not Baseline because it does not work in some of the most widely-used browsers.
Syntax: none | <image>
Initial value: none
| Chrome | Firefox | Safari | Edge | IE |
| :-------------------------------------: | :-----: | :-----------------------------------: | :--------------------------------------: | :-: |
| 1 _(-webkit-mask-box-image-source)_ | No | 17.2 | 79 _(-webkit-mask-box-image-source)_ | No |
| | | 3.1 _(-webkit-mask-box-image-source)_ | | |Content copied to clipboard