diff --git a/src/automath.js b/src/automath.js
index 9a9bf6e6e..e2cf19286 100644
--- a/src/automath.js
+++ b/src/automath.js
@@ -5,7 +5,7 @@ import LiveRange from '@ckeditor/ckeditor5-engine/src/model/liverange';
 import LivePosition from '@ckeditor/ckeditor5-engine/src/model/liveposition';
 import global from '@ckeditor/ckeditor5-utils/src/dom/global';
 
-import { defaultConfig, extractDelimiters, hasDelimiters, delimitersCounts } from './utils';
+import { extractDelimiters, hasDelimiters, delimitersCounts } from './utils';
 
 export default class AutoMath extends Plugin {
 	static get requires() {
@@ -59,7 +59,7 @@ export default class AutoMath extends Plugin {
 	_mathBetweenPositions( leftPosition, rightPosition ) {
 		const editor = this.editor;
 
-		const mathConfig = Object.assign( defaultConfig, this.editor.config.get( 'math' ) );
+		const mathConfig = this.editor.config.get( 'math' );
 
 		const equationRange = new LiveRange( leftPosition, rightPosition );
 		const walker = equationRange.getWalker( { ignoreElementEnd: true } );
diff --git a/src/mathediting.js b/src/mathediting.js
index 61a7c99a1..32a18d906 100644
--- a/src/mathediting.js
+++ b/src/mathediting.js
@@ -1,10 +1,10 @@
 import Plugin from '@ckeditor/ckeditor5-core/src/plugin';
-import { toWidget } from '@ckeditor/ckeditor5-widget/src/utils';
+import { toWidget, viewToModelPositionOutsideModelElement } from '@ckeditor/ckeditor5-widget/src/utils';
 import Widget from '@ckeditor/ckeditor5-widget/src/widget';
 
 import MathCommand from './mathcommand';
 
-import { defaultConfig, renderEquation, extractDelimiters } from './utils';
+import { renderEquation, extractDelimiters } from './utils';
 
 export default class MathEditing extends Plugin {
 	static get requires() {
@@ -21,6 +21,17 @@ export default class MathEditing extends Plugin {
 
 		this._defineSchema();
 		this._defineConverters();
+
+		editor.editing.mapper.on(
+			'viewToModelPosition',
+			viewToModelPositionOutsideModelElement( editor.model, viewElement => viewElement.hasClass( 'math' ) )
+		);
+		editor.config.define( 'math', {
+			engine: 'mathjax',
+			outputType: 'script',
+			forceOutputType: false,
+			enablePreview: true
+		} );
 	}
 
 	_defineSchema() {
@@ -36,7 +47,7 @@ export default class MathEditing extends Plugin {
 
 	_defineConverters() {
 		const conversion = this.editor.conversion;
-		const mathConfig = Object.assign( defaultConfig, this.editor.config.get( 'math' ) );
+		const mathConfig = this.editor.config.get( 'math' );
 
 		// View -> Model
 		conversion.for( 'upcast' )
@@ -114,13 +125,11 @@ export default class MathEditing extends Plugin {
 			const styles = 'user-select: none; ' + ( display ? '' : 'display: inline-block;' );
 			const classes = 'ck-math-tex ' + ( display ? 'ck-math-tex-display' : 'ck-math-tex-inline' );
 
-			// CKEngine render multiple times if using span instead of div
-			const mathtexView = viewWriter.createContainerElement( 'div', {
+			const mathtexView = viewWriter.createContainerElement( 'span', {
 				style: styles,
 				class: classes
 			} );
 
-			// Div is formatted as parent container
 			const uiElement = viewWriter.createUIElement( 'div', null, function( domDocument ) {
 				const domElement = this.toDomElement( domDocument );
 
diff --git a/src/mathui.js b/src/mathui.js
index abd852052..221218710 100644
--- a/src/mathui.js
+++ b/src/mathui.js
@@ -10,7 +10,6 @@ import MainFormView from './ui/mainformview';
 
 // Need math commands from there
 import MathEditing from './mathediting';
-import { defaultConfig } from './utils';
 
 import mathIcon from '../theme/icons/math.svg';
 
@@ -69,7 +68,7 @@ export default class MathUI extends Plugin {
 		const editor = this.editor;
 		const mathCommand = editor.commands.get( 'math' );
 
-		const mathConfig = Object.assign( defaultConfig, this.editor.config.get( 'math' ) );
+		const mathConfig = this.editor.config.get( 'math' );
 
 		const formView = new MainFormView( editor.locale, mathConfig.engine, mathConfig.enablePreview, this._previewUid );
 
@@ -111,7 +110,7 @@ export default class MathUI extends Plugin {
 
 		this._balloon.add( {
 			view: this.formView,
-			position: this._getBalloonPositionData(),
+			position: this._getBalloonPositionData()
 		} );
 
 		if ( this._balloon.visibleView === this.formView ) {
diff --git a/src/utils.js b/src/utils.js
index 812c6f34e..b96385590 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -2,13 +2,6 @@
 
 import global from '@ckeditor/ckeditor5-utils/src/dom/global';
 
-export const defaultConfig = {
-	engine: 'mathjax',
-	outputType: 'script',
-	forceOutputType: false,
-	enablePreview: true
-};
-
 export function getSelectedMathModelWidget( selection ) {
 	const selectedElement = selection.getSelectedElement();
 
@@ -24,7 +17,7 @@ export function isMathJaxVersion3( version ) {
 	return version && typeof version === 'string' && version.split( '.' ).length === 3 && version.split( '.' )[ 0 ] === '3';
 }
 
-// Check if equation has delimiters
+// Check if equation has delimiters.
 export function hasDelimiters( text ) {
 	return text.match( /^(\\\[.*?\\\]|\\\(.*?\\\))$/ );
 }
@@ -108,7 +101,7 @@ function selectRenderMode( element, preview, previewUid, cb ) {
 	}
 }
 
-function renderMathJax3( equation, element, display, after ) {
+function renderMathJax3( equation, element, display, cb ) {
 	let promiseFunction = undefined;
 	if ( typeof MathJax.tex2chtmlPromise !== 'undefined' ) {
 		promiseFunction = MathJax.tex2chtmlPromise;
@@ -122,7 +115,7 @@ function renderMathJax3( equation, element, display, after ) {
 				element.removeChild( element.firstChild );
 			}
 			element.appendChild( node );
-			after();
+			cb();
 		} );
 	}
 }