It looks as if a keylisting interfered with a gpg-agent/scdaemon command.
48458.670390 2024/11/06 12:43:04.238 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread[GUI]::ping()
^ update of the smart cards is requested
48458.670695 2024/11/06 12:43:04.238 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread[2nd]: new iteration command= "__update__" ; nullSlot= true
^ background thread starts update of the smart cards
48459.147743 2024/11/06 12:43:04.728 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread[GUI]::ping()
^ another update of the smart cards is requested (the request is queued)
48464.804883 2024/11/06 12:43:10.393 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread: Card "89490171500022806460" with app "nks" was added 48464.805095 2024/11/06 12:43:10.393 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread: Card "D2760001240100000006154932910000" with app "openpgp" was added 48464.807483 2024/11/06 12:43:10.393 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread: Card "D2760001240100000006154932910000" with app "piv" was added
^ the background thread completed the update of the smart cards and found three card apps
48464.811286 2024/11/06 12:43:10.393 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread[2nd]: new iteration command= "__update__" ; nullSlot= true
^ background thread starts another update of the smart cards
48464.924701 2024/11/06 12:43:10.492 5772 kleopatra.exe org.kde.pim.kleopatra: ReaderStatusThread[GUI]::learnCardsCMS()
^ learn cards is requested (and queued) -> Kleopatra shows the progress overlay
48465.796319 2024/11/06 12:43:11.291 5772 kleopatra.exe org.kde.pim.libkleo: KeyCache::RefreshKeysJob start
^ a keylisting is started (OpenPGP and S/MIME)
48467.549251 2024/11/06 12:43:12.874 5772 kleopatra.exe org.kde.pim.libkleo: sendStatusLinesCommand "SCD LEARN --force" : got ( status( "READER" ) = "SCM Microsystems Inc. SPRx32 USB Smart Card Reader 0" [...] 48467.550423 2024/11/06 12:43:12.875 5772 kleopatra.exe org.kde.pim.libkleo: sendCommand "READKEY --card --no-data -- NKS-NKS3.4531" 48467.895485 2024/11/06 12:43:13.187 5772 kleopatra.exe org.kde.pim.libkleo: sendStatusLinesCommand "READKEY --card --no-data -- NKS-NKS3.4531" : got ( ) 48467.896400 2024/11/06 12:43:13.188 5772 kleopatra.exe org.kde.pim.libkleo: sendCommand "READKEY --card --no-data -- NKS-NKS3.45B1" 48468.209551 2024/11/06 12:43:13.471 5772 kleopatra.exe org.kde.pim.libkleo: sendStatusLinesCommand "READKEY --card --no-data -- NKS-NKS3.45B1" : got ( ) 48468.209660 2024/11/06 12:43:13.471 5772 kleopatra.exe org.kde.pim.libkleo: sendCommand "READKEY --card --no-data -- NKS-NKS3.4571"
^ the background thread sends multiple commands to gpg-agent to gather information about the smart cards
^ the last READKEY command seems to hang
48468.598283 2024/11/06 12:43:13.822 5772 kleopatra.exe org.kde.pim.libkleo: Kleo::KeyCache::RefreshKeysJob(0x63ccba8) RefreshKeysJob::done
^ the keylisting is done