This happens because the development XPC service does not have the required private entitlement to enable message filtering in the sandbox, and therefore fails to apply the sandbox. The existing runtime switching to enable message filtering based on the presence of the entitlement is not working correctly.
<rdar://problem/73382584>
Created attachment 417986 [details] Patch
Created attachment 417989 [details] Patch
Created attachment 417996 [details] Patch
Comment on attachment 417996 [details] Patch r=me
(In reply to Brent Fulgham from comment #5) > Comment on attachment 417996 [details] > Patch > > r=me Thanks for reviewing!
Committed r271710: <https://trac.webkit.org/changeset/271710> All reviewed patches have been landed. Closing bug and clearing flags on attachment 417996 [details].
Comment on attachment 417996 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=417996&action=review > Source/WebKit/WebProcess/com.apple.WebProcess.sb.in:-121 > -#if HAVE(SANDBOX_MESSAGE_FILTERING) I'm surprised by the removal of compile time check. But I guess it's OK given that EWS is green.
(In reply to Alexey Proskuryakov from comment #8) > Comment on attachment 417996 [details] > Patch > > View in context: > https://bugs.webkit.org/attachment.cgi?id=417996&action=review > > > Source/WebKit/WebProcess/com.apple.WebProcess.sb.in:-121 > > -#if HAVE(SANDBOX_MESSAGE_FILTERING) > > I'm surprised by the removal of compile time check. But I guess it's OK > given that EWS is green. This should now be handled at compile time of the sandbox. Thanks for reviewing!