Looking at logs, there are several media accessibility mach-lookup sandbox violations on iOS in the WebContent process.
<rdar://problem/61536195>
Created attachment 396000 [details] Patch
Comment on attachment 396000 [details] Patch Looks sane.
(In reply to Daniel Bates from comment #3) > Comment on attachment 396000 [details] > Patch > > Looks sane. Thanks for reviewing, Dan!
Committed r259869: <https://trac.webkit.org/changeset/259869> All reviewed patches have been landed. Closing bug and clearing flags on attachment 396000 [details].