A bit late to the party, but I just tried #12653 and noticed some non-intuitive behavior (on macOS), that's probably worth explaining release notes and help.

Before this new feature I kept the entire datadir on an SSD drive, so I launch with: `bitcoind -datadir=/Volumes/SSD/Bitcoin`.

Initially I naively moved `/Volumes/SSD/Bitcoin/blocks` to `/Users/bitcoin/blocks` and added a line to `/Volumes/SSD/Bitcoin/bitcoin.conf`: `blocksdir=/Users/bitcoin/blocks`.

I then realized that I shouldn't have moved the `index` subdirectory, so I moved that back to `/Volumes/SSD/Bitcoin/blocks/index`. Having an empty `blocks` dir with just and `index` subdir is a bit weird. Perhaps after @jimpo's #11857 is merged, we could just move / assume all indexes to be there (if `-blocksdir` is set)?

Worse, it created a directory `/Users/bitcoin/blocks/blocks`, which seems like a bug. I had to set `blocksdir=/Users/bitcoin` instead.
{
public:
    explicit CCoinsViewErrorCatcher(CCoinsView* view) : CCoinsViewBacked(view) {}
    bool GetCoin(const COutPoint &outpoint, Coin &coin) const override {
        try {
            return CCoinsViewBacked::GetCoin(outpoint, coin);
        } catch(const std::runtime_error& e) {
            uiInterface.ThreadSafeMessageBox(_("Error reading from database, shutting down."), "", CClientUIInterface::MSG_ERROR);
            LogPrintf("Error reading from database: %s\n", e.what());
            
            
            
            
            abort();
        }
    }
    
};
static std::unique_ptr<CCoinsViewErrorCatcher> pcoinscatcher;
static std::unique_ptr<ECCVerifyHandle> globalVerifyHandle;
static boost::thread_group threadGroup;
static CScheduler scheduler;
void Interrupt()