diff --git a/lib/svgo/plugins.js b/lib/svgo/plugins.js
index dad3ace0..4e0308da 100644
--- a/lib/svgo/plugins.js
+++ b/lib/svgo/plugins.js
@@ -46,7 +46,7 @@ function perItem(data, plugins, reverse) {
         items.content = items.content.filter(function(item) {
 
             // reverse pass
-            if (reverse && item.content && item.elem != 'foreignObject') {
+            if (reverse && item.content) {
                 monkeys(item);
             }
 
@@ -62,7 +62,7 @@ function perItem(data, plugins, reverse) {
             }
 
             // direct pass
-            if (!reverse && item.content && item.elem != 'foreignObject') {
+            if (!reverse && item.content) {
                 monkeys(item);
             }
 
diff --git a/plugins/_collections.js b/plugins/_collections.js
index 46f94bb1..e33695fd 100644
--- a/plugins/_collections.js
+++ b/plugins/_collections.js
@@ -8,7 +8,7 @@ exports.elemsGroups = {
     structural: ['defs', 'g', 'svg', 'symbol', 'use'],
     paintServer: ['solidColor', 'linearGradient', 'radialGradient', 'meshGradient', 'pattern', 'hatch'],
     nonRendering: ['linearGradient', 'radialGradient', 'pattern', 'clipPath', 'mask', 'marker', 'symbol', 'filter', 'solidColor'],
-    container: ['a', 'defs', 'g', 'marker', 'mask', 'missing-glyph', 'pattern', 'svg', 'switch', 'symbol'],
+    container: ['a', 'defs', 'g', 'marker', 'mask', 'missing-glyph', 'pattern', 'svg', 'switch', 'symbol', 'foreignObject'],
     textContent: ['altGlyph', 'altGlyphDef', 'altGlyphItem', 'glyph', 'glyphRef', 'textPath', 'text', 'tref', 'tspan'],
     textContentChild: ['altGlyph', 'textPath', 'tref', 'tspan'],
     lightSource: ['feDiffuseLighting', 'feSpecularLighting', 'feDistantLight', 'fePointLight', 'feSpotLight'],
diff --git a/plugins/removeDoctype.js b/plugins/removeDoctype.js
index da19adf0..8a6a10f0 100644
--- a/plugins/removeDoctype.js
+++ b/plugins/removeDoctype.js
@@ -33,10 +33,6 @@ exports.description = 'removes doctype declaration';
  */
 exports.fn = function(item) {
 
-    // remove doctype only if custom XML entities declaration block does not presents
-    // http://en.wikipedia.org/wiki/Document_Type_Definition#Entity_declarations
-    if (item.doctype && item.doctype.substr(-1) !== ']') {
-        return false;
-    }
+    return false;
 
 };
diff --git a/plugins/removeUnknownsAndDefaults.js b/plugins/removeUnknownsAndDefaults.js
index c7130c84..11d7c3c8 100644
--- a/plugins/removeUnknownsAndDefaults.js
+++ b/plugins/removeUnknownsAndDefaults.js
@@ -36,7 +36,7 @@ for (var elem in elems) {
             if (groupDefaults) {
                 elem.defaults = elem.defaults || {};
 
-                for(var attrName in groupDefaults) {
+                for (var attrName in groupDefaults) {
                     elem.defaults[attrName] = groupDefaults[attrName];
                 }
             }
@@ -74,18 +74,18 @@ exports.fn = function(item, params) {
         if (
             params.unknownContent &&
             !item.isEmpty() &&
-            elems[elem] && //make sure we know of this element before checking its children
-            elem !== 'foreignObject'//Don't check foreignObject
+            elems[elem] && // make sure we know of this element before checking its children
+            elem !== 'foreignObject' // Don't check foreignObject
         ) {
             item.content.forEach(function(content, i) {
                 if (
                     content.isElem() &&
-                    !content.prefix && 
+                    !content.prefix &&
                     (
                         (
                             elems[elem].content && // Do we have a record of its permitted content?
                             elems[elem].content.indexOf(content.elem) === -1
-                        ) || 
+                        ) ||
                         (
                             !elems[elem].content && // we dont know about its permitted content
                             !elems[content.elem] // check that we know about the element at all
@@ -120,7 +120,8 @@ exports.fn = function(item, params) {
                             elems[elem].defaults[attr.name] === attr.value && (
                                 attrsInheritable.indexOf(attr.name) < 0 ||
                                 !item.parentNode.computedAttr(attr.name)
-                        )) ||
+                            )
+                        ) ||
                         // useless overrides
                         (
                             params.uselessOverrides &&