Noticed this while reviewing #13529, but it's also in master @ 5ba77df. On macOS 10.13.6:

<img width="209" alt="schermafbeelding 2018-08-01 om 16 22 09" src="https://user-images.githubusercontent.com/10217/43527498-0f571db4-95a7-11e8-8d90-7863947a7689.png">


<img width="178" alt="schermafbeelding 2018-08-01 om 16 12 51" src="https://user-images.githubusercontent.com/10217/43526994-c9a515ec-95a5-11e8-96b8-9e2513e9aac5.png">

* `Show` in the action menu doesn't work if the app was hidden by `Command + H`, it does work when hidden through this menu
* send and receive don't unhide the window when opened for the action menu. It does navigate to the right tab. The other actions do work (sign, verify & debug window)

Clicking "Toon" (= macOS native show) does work, suggesting the GUI uses some non-native method of hiding.
optionFile << "Type=Application\n";
        if (chain == CBaseChainParams::MAIN)
            optionFile << "Name=Bitcoin\n";
        else
            optionFile << strprintf("Name=Bitcoin (%s)\n", chain);
        optionFile << "Exec=" << pszExePath << strprintf(" -min -testnet=%d -regtest=%d\n", gArgs.GetBoolArg("-testnet", false), gArgs.GetBoolArg("-regtest", false));
        optionFile << "Terminal=false\n";
        optionFile << "Hidden=false\n";
        optionFile.close();
    }
    return true;
}
#elif defined(Q_OS_MAC)
LSSharedFileListItemRef findStartupItemInList(LSSharedFileListRef list, CFURLRef findUrl);
LSSharedFileListItemRef findStartupItemInList(LSSharedFileListRef list, CFURLRef findUrl)
{
    CFArrayRef listSnapshot = LSSharedFileListCopySnapshot(list, nullptr);
    if (listSnapshot == nullptr) {
        return nullptr;
    }
    
    for(int i = 0; i < CFArrayGetCount(listSnapshot); i++) {
        LSSharedFileListItemRef item = (LSSharedFileListItemRef)CFArrayGetValueAtIndex(listSnapshot, i);
        UInt32 resolutionFlags = kLSSharedFileListNoUserInteraction | kLSSharedFileListDoNotMountVolumes;
        CFURLRef currentItemURL = nullptr;
#if defined(MAC_OS_X_VERSION_MAX_ALLOWED) && MAC_OS_X_VERSION_MAX_ALLOWED >= 10100
        if(&LSSharedFileListItemCopyResolvedURL)
            currentItemURL = LSSharedFileListItemCopyResolvedURL(item, resolutionFlags, nullptr);
#if defined(MAC_OS_X_VERSION_MIN_REQUIRED) && MAC_OS_X_VERSION_MIN_REQUIRED < 10100
        else