docs: public WaveformPreview requestWaveformPreviewFrom(final DataReference dataReference) {
          ensureRunning();
          for (WaveformPreview cached : previewHotCache.values()) {
              if (cached.dataReference.equals(dataReference)) {  // Found a hot cue hit, use it.
                  return cached;
              }
          }
          return requestPreviewInternal(dataReference, false);
      }