diff --git a/src/class/container.js b/src/class/container.js
index be0980d9c9..9551188c26 100644
--- a/src/class/container.js
+++ b/src/class/container.js
@@ -76,7 +76,7 @@ Entry.Container = class Container {
             .bindOnClick(() => {
                 Entry.dispatchEvent('openSpriteManager');
             });
-        addButton.innerHTML = Lang.Workspace.add_object;
+        addButton.textContent = Lang.Workspace.add_object;
 
         const ulWrapper = Entry.createElement('div');
         this._view.appendChild(ulWrapper);
diff --git a/src/class/engine.js b/src/class/engine.js
index 49b482c849..5135110468 100644
--- a/src/class/engine.js
+++ b/src/class/engine.js
@@ -141,7 +141,7 @@ Entry.Engine = class Engine {
                     this.blur();
                 })
                 .appendTo(this.buttonWrapper);
-            this.addButton.innerHTML = Lang.Workspace.add_object;
+            this.addButton.textContent = Lang.Workspace.add_object;
             if (!Entry.objectAddable) {
                 this.addButton.addClass('entryRemove');
             }
@@ -151,7 +151,7 @@ Entry.Engine = class Engine {
                 .addClass('entryRunButtonWorkspace_w')
                 .bindOnClick(() => Entry.do('toggleRun', 'runButton'))
                 .appendTo(this.buttonWrapper);
-            this.runButton.innerHTML = Lang.Workspace.run;
+            this.runButton.textContent = Lang.Workspace.run;
 
             this.runButton2 = Entry.createElement('button')
                 .addClass('entryEngineButtonWorkspace_w')
@@ -185,7 +185,7 @@ Entry.Engine = class Engine {
                 .addClass('entryRemove')
                 .bindOnClick(() => Entry.do('toggleStop', 'stopButton'))
                 .appendTo(this.buttonWrapper);
-            this.stopButton.innerHTML = Lang.Workspace.stop;
+            this.stopButton.textContent = Lang.Workspace.stop;
 
             this.stopButton2 = Entry.createElement('button')
                 .addClass('entryEngineButtonWorkspace_w')
@@ -196,7 +196,7 @@ Entry.Engine = class Engine {
                     Entry.engine.toggleStop();
                 })
                 .appendTo(this.buttonWrapper);
-            this.stopButton2.innerHTML = Lang.Workspace.stop;
+            this.stopButton2.textContent = Lang.Workspace.stop;
         } else if (option == 'minimize') {
             /** @type {!Element} */
             this.view_ = controlView;
@@ -228,7 +228,7 @@ Entry.Engine = class Engine {
             this.stopButton.addClass('entryEngineButtonMinimize');
             this.stopButton.addClass('entryStopButtonMinimize');
             this.stopButton.addClass('entryRemove');
-            this.stopButton.innerHTML = Lang.Workspace.stop;
+            this.stopButton.textContent = Lang.Workspace.stop;
             this.view_.appendChild(this.stopButton);
             this.stopButton.bindOnClick(function(e) {
                 this.blur();
@@ -236,7 +236,7 @@ Entry.Engine = class Engine {
             });
 
             this.pauseButton = Entry.createElement('button');
-            this.pauseButton.innerHTML = Lang.Workspace.pause;
+            this.pauseButton.textContent = Lang.Workspace.pause;
             this.pauseButton.addClass('entryEngineButtonMinimize');
             this.pauseButton.addClass('entryPauseButtonMinimize');
             this.pauseButton.addClass('entryRemove');
@@ -314,7 +314,7 @@ Entry.Engine = class Engine {
             if (Entry.objectAddable) {
                 this.runButton.addClass('small');
             }
-            this.runButton.innerHTML = Lang.Workspace.run;
+            this.runButton.textContent = Lang.Workspace.run;
 
             this.footerView_.appendChild(this.runButton);
             this.runButton.bindOnClick((e) => {
@@ -330,7 +330,7 @@ Entry.Engine = class Engine {
             if (Entry.objectAddable) {
                 this.stopButton.addClass('small');
             }
-            this.stopButton.innerHTML = Lang.Workspace.stop;
+            this.stopButton.textContent = Lang.Workspace.stop;
 
             this.footerView_.appendChild(this.stopButton);
             this.stopButton.bindOnClick((e) => {
@@ -368,7 +368,7 @@ Entry.Engine = class Engine {
             const audioShadeText = Entry.createElement('div', 'audioShadeText').addClass(
                 'audioShadeText'
             );
-            audioShadeText.innerHTML = Lang.Msgs.ai_utilize_audio_listening;
+            audioShadeText.textContent = Lang.Msgs.ai_utilize_audio_listening;
             this.audioShadePanel_.appendChild(audioShadeText);
             this.minimizedView_ = document.querySelector('#entryCanvasWrapper');
             if (this.view_.classList[0] === 'entryEngine') {
@@ -490,7 +490,7 @@ Entry.Engine = class Engine {
             this.view_.insertBefore(speedBox, Entry.stage.canvas.canvas);
 
             this.speedLabel_ = Entry.createElement('div', 'entrySpeedLabelWorkspace');
-            this.speedLabel_.innerHTML = Lang.Workspace.speed;
+            this.speedLabel_.textContent = Lang.Workspace.speed;
             speedBox.appendChild(this.speedLabel_);
 
             this.speedProgress_ = Entry.createElement('table', 'entrySpeedProgressWorkspace');
@@ -855,14 +855,14 @@ Entry.Engine = class Engine {
     setPauseButton() {
         if (this.state === EntryEngineState.pause) {
             if (this.pauseButton) {
-                this.pauseButton.innerHTML = Lang.Workspace.restart;
+                this.pauseButton.textContent = Lang.Workspace.restart;
                 if (this.option !== 'minimize') {
                     this.pauseButton.removeClass('entryPauseButtonWorkspace_w');
                     this.pauseButton.addClass('entryRestartButtonWorkspace_w');
                 }
             }
             if (this.pauseButtonFull) {
-                this.pauseButtonFull.innerHTML = Lang.Workspace.restart;
+                this.pauseButtonFull.textContent = Lang.Workspace.restart;
                 if (this.option !== 'minimize') {
                     // workspace && buttonWrapper check
                     if (this.buttonWrapper) {
@@ -875,14 +875,14 @@ Entry.Engine = class Engine {
             }
         } else {
             if (this.pauseButton) {
-                this.pauseButton.innerHTML = Lang.Workspace.pause;
+                this.pauseButton.textContent = Lang.Workspace.pause;
                 if (this.option !== 'minimize') {
                     this.pauseButton.addClass('entryPauseButtonWorkspace_w');
                     this.pauseButton.removeClass('entryRestartButtonWorkspace_w');
                 }
             }
             if (this.pauseButtonFull) {
-                this.pauseButtonFull.innerHTML = Lang.Workspace.pause;
+                this.pauseButtonFull.textContent = Lang.Workspace.pause;
                 if (this.option !== 'minimize') {
                     this.pauseButtonFull.addClass('entryPauseButtonWorkspace_full');
                     this.pauseButtonFull.removeClass('entryRestartButtonWorkspace_full');
diff --git a/src/class/helper.js b/src/class/helper.js
index 71cf3aa22c..47ce947282 100644
--- a/src/class/helper.js
+++ b/src/class/helper.js
@@ -33,7 +33,7 @@ class EntryBlockHelper {
 
         const commandTitle = Entry.createElement('div');
         commandTitle.addClass('entryBlockHelperTitle textModeElem');
-        commandTitle.innerHTML = 'Command';
+        commandTitle.textContent = 'Command';
         blockHelperContent.appendChild(commandTitle);
 
         blockHelperContent.addClass('entryBlockHelperIntro');
@@ -49,7 +49,7 @@ class EntryBlockHelper {
 
         const descTitle = Entry.createElement('div');
         descTitle.addClass('entryBlockHelperTitle textModeElem');
-        descTitle.innerHTML = 'Explanation';
+        descTitle.textContent = 'Explanation';
         blockHelperContent.appendChild(descTitle);
 
         const blockHelperDescription = Entry.createElement(
@@ -58,12 +58,12 @@ class EntryBlockHelper {
         );
         blockHelperDescription.addClass('entryBlockHelperContent selectAble');
         helper.blockHelperContent_.appendChild(blockHelperDescription);
-        blockHelperDescription.innerHTML = Lang.Helper.Block_click_msg;
+        blockHelperDescription.textContent = Lang.Helper.Block_click_msg;
         this.blockHelperDescription_ = blockHelperDescription;
 
         const elementsTitle = Entry.createElement('div');
         elementsTitle.addClass('entryBlockHelperTitle textModeElem');
-        elementsTitle.innerHTML = 'Element';
+        elementsTitle.textContent = 'Element';
         blockHelperContent.appendChild(elementsTitle);
         this._elementsTitle = elementsTitle;
 
@@ -75,7 +75,7 @@ class EntryBlockHelper {
         if (typeof CodeMirror !== 'undefined') {
             const codeMirrorTitle = Entry.createElement('div');
             codeMirrorTitle.addClass('entryBlockHelperTitle textModeElem');
-            codeMirrorTitle.innerHTML = 'Example Code';
+            codeMirrorTitle.textContent = 'Example Code';
             blockHelperContent.appendChild(codeMirrorTitle);
 
             const codeMirrorView = Entry.createElement(
@@ -101,7 +101,7 @@ class EntryBlockHelper {
 
             const codeMirrorDescTitle = Entry.createElement('div');
             codeMirrorDescTitle.addClass('entryBlockHelperTitle textModeElem');
-            codeMirrorDescTitle.innerHTML = 'Example Explanation';
+            codeMirrorDescTitle.textContent = 'Example Explanation';
             blockHelperContent.appendChild(codeMirrorDescTitle);
 
             this._codeMirrorDesc = Entry.createElement('div');
@@ -152,10 +152,10 @@ class EntryBlockHelper {
 
         if (this.workspace.getMode() === Entry.Workspace.MODE_VIMBOARD) {
             this._contentView.addClass('textMode');
-            this.blockHelperDescription_.innerHTML = Lang.PythonHelper[`${type}_desc`];
+            this.blockHelperDescription_.textContent = Lang.PythonHelper[`${type}_desc`];
 
             let elements = Lang.PythonHelper[`${type}_elements`];
-            this._elementsContainer.innerHTML = '';
+            this._elementsContainer.textContent = '';
             if (elements) {
                 this._elementsTitle.removeClass('entryRemove');
                 elements = elements.split('%next');
@@ -166,12 +166,12 @@ class EntryBlockHelper {
                         box.addClass('entryBlockHelperElementsContainer');
                         const left = Entry.createElement('div');
 
-                        left.innerHTML = contents[0];
+                        left.textContent = contents[0];
                         left.addClass('elementLeft');
 
                         const right = Entry.createElement('div');
                         right.addClass('elementRight');
-                        right.innerHTML = contents[1];
+                        right.textContent = contents[1];
                         box.appendChild(left);
                         box.appendChild(right);
                         this._elementsContainer.appendChild(box);
@@ -180,7 +180,7 @@ class EntryBlockHelper {
             } else {
                 this._elementsTitle.addClass('entryRemove');
             }
-            this._codeMirrorDesc.innerHTML = Lang.PythonHelper[`${type}_exampleDesc`];
+            this._codeMirrorDesc.textContent = Lang.PythonHelper[`${type}_exampleDesc`];
 
             const exampleCode = Lang.PythonHelper[`${type}_exampleCode`];
             this._codeMirror.setValue(exampleCode);
@@ -188,7 +188,7 @@ class EntryBlockHelper {
             def = Entry.block[type].pyHelpDef || def;
         } else {
             this._contentView.removeClass('textMode');
-            this.blockHelperDescription_.innerHTML = description;
+            this.blockHelperDescription_.textContent = description;
         }
 
         code.createThread([def]);
diff --git a/src/class/object.js b/src/class/object.js
index b15be90f46..ef55e176e3 100644
--- a/src/class/object.js
+++ b/src/class/object.js
@@ -914,7 +914,7 @@ Entry.EntryObject = class {
             'entryObjectRotateMethodLabelWorkspace'
         );
         rotationMethodWrapper.appendChild(rotateMethodLabelView);
-        rotateMethodLabelView.innerHTML = `${Lang.Workspace.rotate_method}`;
+        rotateMethodLabelView.textContent = `${Lang.Workspace.rotate_method}`;
 
         const rotateModeAView = Entry.createElement('span').addClass(
             'entryObjectRotateModeWorkspace entryObjectRotateModeAWorkspace'
@@ -962,7 +962,7 @@ Entry.EntryObject = class {
             'entryObjectRotateWorkspaceWrapper'
         );
         const rotateSpan = Entry.createElement('span').addClass('entryObjectRotateSpanWorkspace');
-        rotateSpan.innerHTML = `${Lang.Workspace.rotation}`;
+        rotateSpan.textContent = `${Lang.Workspace.rotation}`;
         const RotateDegCoordi = Entry.createElement('span').addClass(
             'entryObjectCoordinateSpanWorkspace degree'
         );
@@ -1001,7 +1001,7 @@ Entry.EntryObject = class {
         const directionSpan = Entry.createElement('span').addClass(
             'entryObjectDirectionSpanWorkspace'
         );
-        directionSpan.innerHTML = `${Lang.Workspace.direction}`;
+        directionSpan.textContent = `${Lang.Workspace.direction}`;
         const DirectionDegCoordi = Entry.createElement('span').addClass(
             'entryObjectCoordinateSpanWorkspace degree'
         );
@@ -1054,7 +1054,7 @@ Entry.EntryObject = class {
             'entryObjectCoordinateWorkspaceWrapper'
         );
         const xCoordi = Entry.createElement('span').addClass('entryObjectCoordinateSpanWorkspace');
-        xCoordi.innerHTML = 'X';
+        xCoordi.textContent = 'X';
         const xInput = Entry.createElement('input').addClass('entryObjectCoordinateInputWorkspace');
         xInput.setAttribute('type', 'text');
         xInput.onkeypress = this.editObjectValueWhenEnterPress;
@@ -1077,11 +1077,11 @@ Entry.EntryObject = class {
             'entryObjectCoordinateWorkspaceWrapper'
         );
         const yCoordi = Entry.createElement('span').addClass('entryObjectCoordinateSpanWorkspace');
-        yCoordi.innerHTML = 'Y';
+        yCoordi.textContent = 'Y';
         const PerCoordi = Entry.createElement('span').addClass(
             'entryObjectCoordinateSpanWorkspace'
         );
-        PerCoordi.innerHTML = '%';
+        PerCoordi.textContent = '%';
         const yInput = Entry.createElement('input').addClass(
             'entryObjectCoordinateInputWorkspace entryObjectCoordinateInputWorkspace_right'
         );
@@ -1105,7 +1105,7 @@ Entry.EntryObject = class {
             'entryObjectCoordinateSizeWrapper'
         );
         const sizeSpan = Entry.createElement('span').addClass('entryObjectCoordinateSizeWorkspace');
-        sizeSpan.innerHTML = `${Lang.Workspace.Size}`;
+        sizeSpan.textContent = `${Lang.Workspace.Size}`;
         const sizeInput = Entry.createElement('input').addClass(
             'entryObjectCoordinateInputWorkspace',
             'entryObjectCoordinateInputWorkspace_size'
diff --git a/src/class/playground.js b/src/class/playground.js
index b65ccfa355..08432d691c 100644
--- a/src/class/playground.js
+++ b/src/class/playground.js
@@ -72,7 +72,7 @@ Entry.Playground = class Playground {
             const curtainView = Entry.createElement('div', 'entryCurtain')
                 .addClass('entryPlaygroundCurtainWorkspace entryRemove')
                 .appendTo(this.view_);
-            curtainView.innerHTML = Lang.Workspace.cannot_edit_click_to_stop;
+            curtainView.textContent = Lang.Workspace.cannot_edit_click_to_stop;
             curtainView.addEventListener('click', () => {
                 Entry.engine.toggleStop();
             });
@@ -92,7 +92,7 @@ Entry.Playground = class Playground {
             const pictureCurtainText = Entry.createElement('span', 'entryPictureCurtainText')
                 .addClass('entryPlaygroundPictureCurtainWorkspaceText')
                 .appendTo(pictureCurtainView);
-            pictureCurtainText.innerHTML = Lang.Workspace.add_object_before_edit;
+            pictureCurtainText.textContent = Lang.Workspace.add_object_before_edit;
 
             const textView = Entry.createElement('div', 'entryText')
                 .addClass('entryPlaygroundTextWorkspace entryRemove')
@@ -172,7 +172,7 @@ Entry.Playground = class Playground {
                 Entry.do('playgroundChangeViewMode', 'code', that.selectedViewMode);
             })
             .appendTo(tabList);
-        codeTab.innerHTML = Lang.Workspace.tab_code;
+        codeTab.textContent = Lang.Workspace.tab_code;
         this.tabViewElements.code = codeTab;
         this._codeTab = codeTab;
 
@@ -182,7 +182,7 @@ Entry.Playground = class Playground {
                 Entry.do('playgroundChangeViewMode', 'picture', that.selectedViewMode);
             })
             .appendTo(tabList);
-        pictureTab.innerHTML = Lang.Workspace.tab_picture;
+        pictureTab.textContent = Lang.Workspace.tab_picture;
         this.tabViewElements.picture = pictureTab;
         this.pictureTab = pictureTab;
 
@@ -192,7 +192,7 @@ Entry.Playground = class Playground {
             .bindOnClick(() => {
                 Entry.do('playgroundChangeViewMode', 'text', that.selectedViewMode);
             });
-        textboxTab.innerHTML = Lang.Workspace.tab_text;
+        textboxTab.textContent = Lang.Workspace.tab_text;
         this.tabViewElements.text = textboxTab;
         this.textboxTab = textboxTab;
 
@@ -202,7 +202,7 @@ Entry.Playground = class Playground {
             .bindOnClick(() => {
                 Entry.do('playgroundChangeViewMode', 'sound', that.selectedViewMode);
             });
-        soundTab.innerHTML = Lang.Workspace.tab_sound;
+        soundTab.textContent = Lang.Workspace.tab_sound;
         this.tabViewElements.sound = soundTab;
         this.soundTab = soundTab;
 
@@ -212,7 +212,7 @@ Entry.Playground = class Playground {
             .bindOnClick(() => {
                 Entry.do('playgroundChangeViewMode', 'variable', that.selectedViewMode);
             });
-        variableTab.innerHTML = Lang.Workspace.tab_attribute;
+        variableTab.textContent = Lang.Workspace.tab_attribute;
         this.tabViewElements.variable = variableTab;
         this.variableTab = variableTab;
     }
@@ -643,7 +643,7 @@ Entry.Playground = class Playground {
                     }
                 })
                 .appendTo(pictureAdd);
-            innerPictureAdd.innerHTML = Lang.Workspace.picture_add;
+            innerPictureAdd.textContent = Lang.Workspace.picture_add;
             this._pictureAddButton = innerPictureAdd;
 
             const innerDrawNewPicture = Entry.createElement('div', 'entryNewPictureInner')
@@ -652,7 +652,7 @@ Entry.Playground = class Playground {
                     this.painter.newPicture();
                 })
                 .appendTo(pictureAdd);
-            innerDrawNewPicture.innerHTML = Lang.Workspace.draw_new;
+            innerDrawNewPicture.textContent = Lang.Workspace.draw_new;
             this._drawNewPictureButton = innerDrawNewPicture;
 
             this.pictureListView_ = Entry.createElement('ul', 'entryPictureList')
@@ -903,7 +903,7 @@ Entry.Playground = class Playground {
         this.fontSizeWrapper = fontSizeWrapper;
 
         const fontSizeLabel = Entry.createElement('div').addClass('entryPlaygroundFontSizeLabel');
-        fontSizeLabel.innerHTML = Lang.General.font_size;
+        fontSizeLabel.textContent = Lang.General.font_size;
         fontSizeWrapper.appendChild(fontSizeLabel);
 
         const fontSizeSlider = Entry.createElement('div').addClass('entryPlaygroundFontSizeSlider');
@@ -1039,7 +1039,7 @@ Entry.Playground = class Playground {
         const tempNotification = Entry.createElement('span').addClass(
             'entryPlaygroundSoundEditText'
         );
-        tempNotification.innerHTML = Lang.Menus.sound_edit_warn;
+        tempNotification.textContent = Lang.Menus.sound_edit_warn;
 
         tempNotificationWrapper.appendChild(tempImage);
         tempNotificationWrapper.appendChild(tempNotification);
@@ -1072,7 +1072,7 @@ Entry.Playground = class Playground {
                     );
                 }
             });
-            innerSoundAdd.innerHTML = Lang.Workspace.sound_add;
+            innerSoundAdd.textContent = Lang.Workspace.sound_add;
             soundAdd.appendChild(innerSoundAdd);
             soundView.appendChild(soundAdd);
             const soundList = Entry.createElement('ul', 'entrySoundList').addClass(
@@ -1234,7 +1234,7 @@ Entry.Playground = class Playground {
             (this.object.pictures || []).forEach((picture, i) => {
                 !picture.view && Entry.playground.generatePictureElement(picture);
                 const element = picture.view;
-                element.orderHolder.innerHTML = i + 1;
+                element.orderHolder.textContent = i + 1;
             });
 
             isSelect && this.selectPicture(this.object.selectedPicture);
@@ -1292,7 +1292,7 @@ Entry.Playground = class Playground {
                 )}/thumb/${fileName}.png")`;
             }
             const sizeView = $element.find(`#s_${picture.id}`)[0];
-            sizeView.innerHTML = `${picture.dimension.width} X ${picture.dimension.height}`;
+            sizeView.textContent = `${picture.dimension.width} X ${picture.dimension.height}`;
         }
 
         Entry.container.setPicture(picture);
@@ -1434,7 +1434,7 @@ Entry.Playground = class Playground {
             (this.object.sounds || []).forEach((sound, i) => {
                 !sound.view && Entry.playground.generateSoundElement(sound);
                 const element = sound.view;
-                element.orderHolder.innerHTML = i + 1;
+                element.orderHolder.textContent = i + 1;
             });
         }
 
@@ -1898,7 +1898,7 @@ Entry.Playground = class Playground {
             .addClass('entryPlaygroundPictureSize')
             .appendTo(
                 element
-            ).innerHTML = `${picture.dimension.width} X ${picture.dimension.height}`;
+            ).textContent = `${picture.dimension.width} X ${picture.dimension.height}`;
 
         const removeButton = Entry.createElement('div').addClass('entryPlayground_del');
         const { Buttons = {} } = Lang || {};
@@ -2063,7 +2063,7 @@ Entry.Playground = class Playground {
         nameView.onkeypress = Entry.Utils.blurWhenEnter;
         Entry.createElement('div')
             .addClass('entryPlaygroundSoundLength')
-            .appendTo(element).innerHTML = `${sound.duration} ${Lang.General.second}`;
+            .appendTo(element).textContent = `${sound.duration} ${Lang.General.second}`;
         const removeButton = Entry.createElement('div').addClass('entryPlayground_del');
         const { Buttons = {} } = Lang || {};
         const { delete: delText = '삭제' } = Buttons;
diff --git a/src/class/toast.js b/src/class/toast.js
index cdd84a60a4..d885626146 100644
--- a/src/class/toast.js
+++ b/src/class/toast.js
@@ -105,8 +105,8 @@ Entry.Toast = class Toast {
         toastMessage.addClass('entryToastMessage');
 
         if (Array.isArray(message)) {
-            toastMessage.innerHTML = message.reduce(
-                (total, current) => `${total}<br/>${current}`,
+            toastMessage.textContent = message.reduce(
+                (total, current) => `${total}\n${current}`,
                 ''
             );
         } else {
diff --git a/src/css/components/playground.less b/src/css/components/playground.less
index ac1a719e68..e5257fb9bb 100644
--- a/src/css/components/playground.less
+++ b/src/css/components/playground.less
@@ -202,15 +202,8 @@
         z-index: 400;
         background-color: rgba(248, 241, 204, 0.9);
         border: 2px dashed #ffc800;
-        -webkit-box-pack: center;
-        -ms-flex-pack: center;
         justify-content: center;
-        -webkit-box-align: center;
-        -ms-flex-align: center;
         align-items: center;
-        -webkit-box-orient: vertical;
-        -webkit-box-direction: normal;
-        -ms-flex-direction: column;
         flex-direction: column;
 
         .blockBackPackIcon {
@@ -415,6 +408,7 @@
     opacity: 0.5;
     z-index: 255;
     cursor: pointer;
+    white-space: pre-line;
 }
 
 .entryPlaygroundCurtainPhone {
@@ -452,15 +446,10 @@
     font-weight: bold;
     line-height: 1.33;
     letter-spacing: -0.6px;
-    display: -webkit-box;
-    display: -ms-flexbox;
     display: flex;
-    -webkit-box-pack: center;
-    -ms-flex-pack: center;
     justify-content: center; /* align horizontal */
-    -webkit-box-align: center;
-    -ms-flex-align: center;
     align-items: center; /* align vertical */
+    white-space: pre-line;
 }
 
 .entryPlaygroundTableCurtainWorkspace {
@@ -484,14 +473,8 @@
     font-weight: bold;
     line-height: 1.33;
     letter-spacing: -0.6px;
-    display: -webkit-box;
-    display: -ms-flexbox;
     display: flex;
-    -webkit-box-pack: center;
-    -ms-flex-pack: center;
     justify-content: center; /* align horizontal */
-    -webkit-box-align: center;
-    -ms-flex-align: center;
     align-items: center; /* align vertical */
 }
 
@@ -638,6 +621,11 @@
     cursor: pointer;
 }
 
+.entryPlaygroundPictureElement::-moz-selection {
+    cursor: move;
+    background-color: #fff;
+}
+
 .entryPlaygroundPictureElement::selection {
     cursor: move;
     background-color: #fff;
@@ -692,7 +680,6 @@
     cursor: text;
     border: 1px solid #e2e2e2;
     border-radius: 4px;
-    -webkit-box-sizing: border-box;
     box-sizing: border-box;
 }
 .entryPlaygroundPictureName:focus,
@@ -764,7 +751,6 @@
     }
 }
 .pop_selectbox * {
-    -webkit-box-sizing: content-box;
     box-sizing: content-box;
 }
 .pop_selectbox .tooltip_box {
@@ -1103,14 +1089,8 @@
     overflow: hidden;
     border-left: 1px solid #e2e2e2;
     background-color: #f2f2f2;
-    display: -webkit-box;
-    display: -ms-flexbox;
     display: flex;
-    -webkit-box-pack: center;
-    -ms-flex-pack: center;
     justify-content: center;
-    -webkit-box-align: center;
-    -ms-flex-align: center;
     align-items: center;
 
     .entryPlaygroundSoundEditWrapper {
@@ -1141,6 +1121,7 @@
         -moz-user-select: none;
         -ms-user-select: none;
         user-select: none;
+        white-space: pre-line;
     }
 }
 
@@ -1255,7 +1236,6 @@
 .entryPlaygroundSoundName {
     width: 100%;
     height: 24px;
-    -webkit-box-sizing: border-box;
     box-sizing: border-box;
     margin-top: 10px;
     padding: 0 4px;
@@ -1332,7 +1312,6 @@
     width: 136px;
     height: 8px;
     border-radius: 3px;
-    -webkit-box-shadow: inset 1px 1px 1px 0 rgba(0, 0, 0, 0.03);
     box-shadow: inset 1px 1px 1px 0 rgba(0, 0, 0, 0.03);
     background-color: #d8d8d8;
 }
@@ -1479,14 +1458,8 @@
     overflow: hidden;
     border-left: 1px solid #e2e2e2;
     background-color: #f2f2f2;
-    display: -webkit-box;
-    display: -ms-flexbox;
     display: flex;
-    -webkit-box-pack: center;
-    -ms-flex-pack: center;
     justify-content: center;
-    -webkit-box-align: center;
-    -ms-flex-align: center;
     align-items: center;
 
     .entryPlaygroundTableEditWrapper {
@@ -1633,7 +1606,6 @@
     .entryPlaygroundTableName {
         width: 100%;
         height: 24px;
-        -webkit-box-sizing: border-box;
         box-sizing: border-box;
         margin-top: 12px;
         padding: 0 4px;
diff --git a/src/css/components/toast.less b/src/css/components/toast.less
index 6e46ae5527..3ca2e308ae 100644
--- a/src/css/components/toast.less
+++ b/src/css/components/toast.less
@@ -51,6 +51,7 @@
     font-size: 9pt;
     margin-top: 4px;
     margin-bottom: 2px;
+    white-space: pre-line;
 }
 
 .entryMobileToastWrapper {
diff --git a/src/playground/block_menu.ts b/src/playground/block_menu.ts
index 15e5f920da..a9b7a3bd32 100644
--- a/src/playground/block_menu.ts
+++ b/src/playground/block_menu.ts
@@ -1361,7 +1361,7 @@ class BlockMenu extends ModelClass<Schema> {
                 class: 'entryCategoryListWorkspace',
             });
         } else {
-            this.categoryWrapper.innerHTML = '';
+            this.categoryWrapper.textContent = '';
         }
 
         this._categoryCol = Entry.Dom('ul', {
diff --git a/src/playground/blocks/block_expansion_festival.js b/src/playground/blocks/block_expansion_festival.js
index 9da0b0d899..34e4b4fc69 100644
--- a/src/playground/blocks/block_expansion_festival.js
+++ b/src/playground/blocks/block_expansion_festival.js
@@ -326,9 +326,7 @@ Entry.EXPANSION_BLOCK.festival = {
         overview: 'overview',
     },
     strip(html) {
-        const tmp = document.createElement('DIV');
-        tmp.innerHTML = html;
-        return tmp.textContent || tmp.innerText || '';
+        return Entry.Utils.extractTextFromHTML(html);
     },
     monthMap: {
         January: 1,
@@ -437,7 +435,10 @@ Entry.EXPANSION_BLOCK.festival.getBlocks = function() {
         return new PromiseManager().Promise((resolve) => {
             callApi(key, { url: `${Entry.EXPANSION_BLOCK.festival.api}/${contentid}` })
                 .then((response) => {
-                    const item = response.data.response.body.items.item;
+                    let item = response.data.response.body.items.item;
+                    if (Array.isArray(item)) {
+                        item = item[0];
+                    }
                     if (item && item[infoType]) {
                         return resolve(Entry.EXPANSION_BLOCK.festival.strip(item[infoType]));
                     }
diff --git a/src/util/htmlElementPatcher.js b/src/util/htmlElementPatcher.js
index 45cd7cea14..636630f6fb 100644
--- a/src/util/htmlElementPatcher.js
+++ b/src/util/htmlElementPatcher.js
@@ -14,7 +14,7 @@
 
     p.text = function(str) {
         if (str) {
-            this.innerHTML = str;
+            this.textContent = str;
         }
         return this;
     };
diff --git a/src/util/utils.js b/src/util/utils.js
index d4c366dc3a..3a802dfdbb 100644
--- a/src/util/utils.js
+++ b/src/util/utils.js
@@ -1381,7 +1381,7 @@ Entry.computeInputWidth = (function() {
                 document.body.appendChild(elem);
             }
 
-            elem.innerHTML = value;
+            elem.textContent = value;
             const ret = `${Number(elem.offsetWidth + 10)}px`;
 
             if (window.fontLoaded) {
@@ -3051,3 +3051,9 @@ Entry.Utils.doCodeChange = () => {
         Entry.codeChangedEvent.notify();
     }
 };
+
+Entry.Utils.extractTextFromHTML = (htmlString) => {
+    const parser = new DOMParser();
+    const dom = parser.parseFromString(htmlString, 'text/html');
+    return dom.body.textContent || '';
+};
diff --git a/types/index.d.ts b/types/index.d.ts
index 3d08339688..1bd4ffff12 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -64,6 +64,7 @@ declare interface EntryDomOptions {
 
 declare interface EntryDom extends JQuery {
     innerHTML?: string;
+    textContent?: string;
     bindOnClick?: (e: any) => this;
 }