@jonasschnelli wrote in #14979:
> #14573 broke < Qt5.6 compatibility due to calling the lambda version of `addAction` that was added in Qt5.6.

We currently [support](https://github.com/bitcoin/bitcoin/blob/master/doc/dependencies.md) QT >=5.2, but hardly anyone tests with that. If we make one of the Travis machines use it, we should have a better change of catching this.

See also discussion about minimum QT version in #13478 
{
        LOCK(m_wallet.cs_wallet);
        std::vector<WalletAddress> result;
        for (const auto& item : m_wallet.mapAddressBook) {
            result.emplace_back(item.first, IsMine(m_wallet, item.first), item.second.name, item.second.purpose);
        }
        return result;
    }
    void learnRelatedScripts(const CPubKey& key, OutputType type) override { m_wallet.LearnRelatedScripts(key, type); }
    bool addDestData(const CTxDestination& dest, const std::string& key, const std::string& value) override
    {
        LOCK(m_wallet.cs_wallet);
        return m_wallet.AddDestData(dest, key, value);
    }
    bool eraseDestData(const CTxDestination& dest, const std::string& key) override
    {
        LOCK(m_wallet.cs_wallet);
        return m_wallet.EraseDestData(dest, key);
    }
    std::vector<std::string> getDestValues(const std::string& prefix) override