As I understand it, we upgraded a dependency, but the new version relies on certain methods that aren’t available in some browser contexts. The fix is to use something called a polyfill; a scripted method to deliver the same result even if the “native” method isn’t available on a particular browser.
The release note item calls out iOS, but we’ve seen reports of issues on other systems: Nightly 8.1 Changelogs - 2021 - #94 by sreis
Projected release of 8.1.8 final is early August.