Running LibreOffice 22.214.171.124 on Mac OS 10.15.7 with GPGTools 2020.1.
No PGP keys/signatures are found when LibreOffice is started from Launchpad, Spotlight or directly via double click on ODF file.
This is both visible in the settings when no predefined PGP key can be chosen, and in the signature dialog, when no PGP is offered.
Starting LibreOffice via "open /Applications/LibreOffice.app", or "open file.odt" or "/Applications/LibreOffice.app/Contents/MacOS/soffice" does find the key.
Steps to Reproduce:
1. Open LibreOffice
2. Go to Preferences -> LibreOffice -> User Data -> Cryptography
Only option displayed is "No Key"
Ability to select predefined OpenPGP key
User Profile Reset: Yes
[Information automatically included from LibreOffice]
[Information guessed from browser]
OS: Mac OS X (All)
OS is 64bit: no
*** This bug has been marked as a duplicate of bug 115538 ***