Running deprecation trial for "Remove alert(), confirm(), and prompt for cross origin iframes"

[Carlos IL]

Hi experimentation-dev,

After receiving approval on the intent to run a deprecation trial, (https://groups.google.com/a/chromium.org/g/blink-dev/c/VOePv--Qa-4/m/uoTP-h4-BAAJ), we are planning to run a trial to delay this deprecation temporarily, starting in M92 and until M96.

Thanks,

-Carlos