diff --git a/src/rich_text_editor/index.ts b/src/rich_text_editor/index.ts
index 285e403e9..996368f88 100644
--- a/src/rich_text_editor/index.ts
+++ b/src/rich_text_editor/index.ts
@@ -41,7 +41,7 @@ import { Module } from '../abstract';
 import { Debounced, Model } from '../common';
 import ComponentView from '../dom_components/view/ComponentView';
 import EditorModel from '../editor/model/Editor';
-import { removeEl } from '../utils/dom';
+import { createEl, cx, removeEl } from '../utils/dom';
 import { hasWin, isDef, on } from '../utils/mixins';
 import defaults, { RichTextEditorConfig } from './config/config';
 import RichTextEditor, { RichTextEditorAction } from './model/RichTextEditor';
@@ -116,6 +116,7 @@ export default class RichTextEditorModule extends Module<RichTextEditorConfig &
     super(em, 'RichTextEditor', defaults);
     const { config } = this;
     const ppfx = config.pStylePrefix;
+    const isCustom = config.custom;
 
     if (ppfx) {
       config.stylePrefix = ppfx + config.stylePrefix;
@@ -128,10 +129,11 @@ export default class RichTextEditorModule extends Module<RichTextEditorConfig &
     model.on('change:currentView', this.__trgCustom, this);
     this.__dbdTrgCustom = debounce(() => this.__trgCustom(), 0);
     if (!hasWin()) return this;
-    const toolbar = document.createElement('div');
-    toolbar.className = `${ppfx}rte-toolbar ${ppfx}one-bg`;
+    const toolbar = createEl('div', {
+      class: cx(`${ppfx}rte-toolbar`, !isCustom && `${ppfx}one-bg`),
+    });
     this.toolbar = toolbar;
-    this.initRte(document.createElement('div'));
+    this.initRte(createEl('div'));
 
     //Avoid closing on toolbar clicking
     on(toolbar, 'mousedown', e => e.stopPropagation());
diff --git a/src/utils/dom.ts b/src/utils/dom.ts
index bfc8d9299..4da47c8c1 100644
--- a/src/utils/dom.ts
+++ b/src/utils/dom.ts
@@ -9,6 +9,10 @@ type vNode = {
 
 type ChildHTML = HTMLElement | string;
 
+type ClassNameInputType = string | number | boolean | null | undefined;
+
+type ClassNameInput = ClassNameInputType | Array<ClassNameInputType>;
+
 const KEY_TAG = 'tag';
 const KEY_ATTR = 'attributes';
 const KEY_CHILD = 'children';
@@ -22,6 +26,11 @@ export const removeEl = (el?: HTMLElement) => {
   parent && parent.removeChild(el);
 };
 
+export function cx(...inputs: ClassNameInput[]): string {
+  const inp = Array.isArray(inputs[0]) ? inputs[0] : [...inputs];
+  return inp.filter(Boolean).join(' ');
+}
+
 export const find = (el: HTMLElement, query: string) => el.querySelectorAll(query);
 
 export const attrUp = (el?: HTMLElement, attrs: ObjectAny = {}) =>