Cannot import into the keychain when double-clicking the .p12 certificate
Use the following command line, after that, reopen the keychain and add it
security import certificate name.p12 -k ~/Library/Keychains/login.keychain
note:
Security is a command line management tool for keychains and security modules in Mac systems
import adds a key to the keychain (authenticated entity)
-
-k
<keychain>specifies which keychain to import the project into