diff --git a/browser/main/lib/ConfigManager.js b/browser/main/lib/ConfigManager.js
index bea019fa9..32a6f86c0 100644
--- a/browser/main/lib/ConfigManager.js
+++ b/browser/main/lib/ConfigManager.js
@@ -83,7 +83,7 @@ export const DEFAULT_CONFIG = {
     breaks: true,
     smartArrows: false,
     allowCustomCSS: false,
-    customCSS: '',
+    customCSS: '/* Drop Your Custom CSS Code Here */',
     sanitize: 'STRICT', // 'STRICT', 'ALLOW_STYLES', 'NONE'
     lineThroughCheckbox: true
   },
@@ -152,7 +152,13 @@ function get () {
 
 function set (updates) {
   const currentConfig = get()
-  const newConfig = Object.assign({}, DEFAULT_CONFIG, currentConfig, updates)
+
+  const arrangedUpdates = updates
+  if (updates.preview !== undefined && updates.preview.customCSS === '') {
+    arrangedUpdates.preview.customCSS = DEFAULT_CONFIG.preview.customCSS
+  }
+
+  const newConfig = Object.assign({}, DEFAULT_CONFIG, currentConfig, arrangedUpdates)
   if (!validate(newConfig)) throw new Error('INVALID CONFIG')
   _save(newConfig)
 
diff --git a/browser/main/modals/PreferencesModal/UiTab.js b/browser/main/modals/PreferencesModal/UiTab.js
index f74dbda52..c82cac175 100644
--- a/browser/main/modals/PreferencesModal/UiTab.js
+++ b/browser/main/modals/PreferencesModal/UiTab.js
@@ -883,7 +883,6 @@ class UiTab extends React.Component {
                   onChange={e => this.handleUIChange(e)}
                   ref={e => (this.customCSSCM = e)}
                   value={config.preview.customCSS}
-                  defaultValue={'/* Drop Your Custom CSS Code Here */\n'}
                   options={{
                     lineNumbers: true,
                     mode: 'css',