@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 
if (rescan_height != block_height) {
                InitError(_("Prune: last wallet synchronisation goes beyond pruned data. You need to -reindex (download the whole blockchain again in case of pruned node)"));
                return nullptr;
            }
        }
        uiInterface.InitMessage(_("Rescanning..."));
        walletInstance->WalletLogPrintf("Rescanning last %i blocks (from block %i)...\n", *tip_height - rescan_height, rescan_height);
        
        
        if (walletInstance->nTimeFirstKey) {
            if (Optional<int> first_block = locked_chain->findFirstBlockWithTimeAndHeight(walletInstance->nTimeFirstKey - TIMESTAMP_WINDOW, rescan_height)) {
                rescan_height = *first_block;
            }
        }
        nStart = GetTimeMillis();
        {
            WalletRescanReserver reserver(walletInstance.get());
            if (!reserver.reserve() || (ScanResult::SUCCESS != walletInstance->ScanForWalletTransactions(locked_chain->getBlockHash(rescan_height), {} , reserver, true ).status)) {
                InitError(_("Failed to rescan the wallet during initialization"));
                return nullptr;
            }
        }
        walletInstance->WalletLogPrintf("Rescan completed in %15dms\n", GetTimeMillis() - nStart);
        walletInstance->ChainStateFlushed(locked_chain->getLocator());
        walletInstance->database->IncrementUpdateCounter();
        
        if (gArgs.GetBoolArg("-zapwallettxes", false) && gArgs.GetArg("-zapwallettxes", "1") != "2")
        {
            WalletBatch batch(*walletInstance->database);
            for (const CWalletTx& wtxOld : vWtx)