Today I downloaded the Mac version 4.3.5002 and all was going well. Then I tried to open the app and was given the message: "LibreOffice.app" can't be opened because the identity of the developer cannot be confirmed. This happened when I downloaded from libreoffice.org. So I returned and downloaded from download.documentfoundation.org and received the same message.
This is an update from a previous version which I chose to replace so the earlier version of LibreOffice.app was removed and now I cannot access any of my several documents in LibreOffice
*** This bug has been marked as a duplicate of bug 84352 ***