There are no issues of vanishing notifications on my end. And dude, you could just install the dev beta profile from here and try testing these things yourself first instead of only posting in a thread asking if the issue still persists and not test it in the new beta.Can anyone test the issue of vanishing notifications on this beta. I am not on developer beta and am unable to wait for public beta to know about this issue.
The issue is - clear all notifications from notification centre by clicking ,clear button multiple times at the top right of notification centre.
Then receive a mail notification in NC. Now open mail app. This opening and closing of mail app will clear the NC of the mail notifications showing there.