In trying to debug #12337 I added a sleep at the end of AppInitMain() to simulate being able to close the application late in the AppInitMain() process. If I close the splash screen at this point, I get a reliable crash when the splashs screen is deleted as it tries to disconnect itself from the wallet ShowProgress signal after Shutdown() has been called and the wallet has been deleted.
{
    try
    {
        qDebug() << __func__ << ": Running initialization in thread";
        bool rv = AppInitMain();
        Q_EMIT initializeResult(rv);
    } catch (const std::exception& e) {
        handleRunawayException(&e);
    } catch (...) {
        handleRunawayException(nullptr);
    }
}
void BitcoinCore::shutdown()
{
    try
    {
        qDebug() << __func__ << ": Running Shutdown in thread";
        Interrupt();
        Shutdown();
        qDebug() << __func__ << ": Shutdown finished";
        Q_EMIT shutdownResult();
    } catch (const std::exception& e) {
        handleRunawayException(&e);
    } catch (...) {
        handleRunawayException(nullptr);
    }
}
BitcoinApplication::BitcoinApplication(int &argc, char **argv):