try an even better fix

etpinard · etpinard · commit 08069a484680 · 2016-10-26T18:09:13.000-04:00
diff --git a/src/plot_api/plot_api.js b/src/plot_api/plot_api.js
@@ -1822,13 +1822,11 @@ function _relayout(gd, aobj) {
         undoit[ai] = (pleaf === 'reverse') ? vi : p.get();
 
         // Setting width or height to null must reset the graph's width / height
-        // back to its initial value as listed in attribute declaration.
+        // back to its initial value as computed during the first pass in Plots.plotAutoSize.
         //
-        // We must manually set them back here, because we can't rely on
-        // Plots.plotAutoSize as it falls back to computing width / height values
-        // from the DOM which can have been changed by other relayout calls.
+        // To do so, we must manually set them back here using the _initialAutoSize cache.
         if(['width', 'height'].indexOf(ai) !== -1 && vi === null) {
-            gd._fullLayout[ai] = Plots.layoutAttributes[ai].dflt;
+            gd._fullLayout[ai] = gd._initialAutoSize[ai];
         }
         // check autorange vs range
         else if(pleafPlus.match(/^[xyz]axis[0-9]*\.range(\[[0|1]\])?$/)) {
diff --git a/src/plots/plots.js b/src/plots/plots.js
@@ -998,6 +998,12 @@ plots.plotAutoSize = function plotAutoSize(gd, layout, fullLayout) {
         if(heightHasChanged) fullLayout.height = newHeight;
     }
 
+    // cache initial autosize value, used in relayout when
+    // width or height values are set to null
+    if(!gd._initialAutoSize) {
+        gd._initialAutoSize = { width: newWidth, height: newHeight };
+    }
+
     plots.sanitizeMargins(fullLayout);
 };
 
@@ -1117,6 +1123,7 @@ plots.purge = function(gd) {
     delete gd._lastHoverTime;
     delete gd._transitionData;
     delete gd._transitioning;
+    delete gd._initialAutoSize;
 
     // remove all event listeners
     if(gd.removeAllListeners) gd.removeAllListeners();
