anchor.diff:          // Start our chain of methods
           findSelectionMatches();
           function findSelectionMatches() {
  +          // Start our performance check (70ms for 200 1024x1600 images)
  +          console.time('findSelectionMatches');
  +
             // Find our sets of images to update
             var compareSetEls = document.querySelectorAll('[data-compare-set]');
   
  
positive.code:             return true;
            });
  
            // Pass through matching sets to `bulkUpdateSelection`
            bulkUpdateSelection(matchingCompareSets);
          }
  
          function bulkUpdateSelection(compareSets) {
            // Find our output targets
            var resultsEl = document.querySelector('#results');
            var resultsDocFrag = document.createDocumentFragment();
  
negative.code:             //   Extract image from 2nd canvas via `ndarray`
              //   Use web workers
              //   Requesting server do it via `get-pixels` and `save-pixels`
              // DEV: Slowest part is drawing initial image above
              // https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/rect
              context.rect(targetArea.left, targetArea.top, targetArea.width, targetArea.height);
              context.clip();
  