https://caniuse.com/#feat=css-masks
If I am wrong, it would make my day.
Edge dev isnt far off Chrome canary
edge supports 42% of masking tags, chrome 41%. Chrome has slightly more coverage of mask tags but edge has more complete support for masking tags.
I use the Edge browser on windows 10 to view PDF’s.
All I know is that I had a project recently that involved SVG masking and Edge was the only browser that did not support it.