diff --git a/umap/static/umap/js/modules/panel.js b/umap/static/umap/js/modules/panel.js
index b83d703d..d2ea1918 100644
--- a/umap/static/umap/js/modules/panel.js
+++ b/umap/static/umap/js/modules/panel.js
@@ -2,13 +2,12 @@ import { DomUtil, DomEvent } from '../../vendors/leaflet/leaflet-src.esm.js'
 import { translate } from './i18n.js'
 
 export class Panel {
-  MODE = 'condensed'
-  CLASSNAME = 'left'
-
   constructor(map) {
     this.parent = map._container
     this.map = map
     this.container = DomUtil.create('div', '', this.parent)
+    this.mode = 'condensed'
+    this.classname = 'left'
     DomEvent.disableClickPropagation(this.container)
     DomEvent.on(this.container, 'contextmenu', DomEvent.stopPropagation) // Do not activate our custom context menu.
     DomEvent.on(this.container, 'wheel', DomEvent.stopPropagation)
@@ -16,7 +15,7 @@ export class Panel {
   }
 
   open(e) {
-    this.container.className = `with-transition panel ${this.CLASSNAME} ${this.MODE}`
+    this.container.className = `with-transition panel ${this.classname} ${this.mode}`
     this.container.innerHTML = ''
     const actionsContainer = DomUtil.create('ul', 'toolbox', this.container)
     const body = DomUtil.create('div', 'body', this.container)
@@ -45,12 +44,12 @@ export class Panel {
   }
 
   resize() {
-    if (this.MODE === 'expanded') {
-      this.MODE = 'condensed'
+    if (this.mode === 'expanded') {
+      this.mode = 'condensed'
       this.container.classList.remove('expanded')
       this.container.classList.add('condensed')
     } else {
-      this.MODE = 'expanded'
+      this.mode = 'expanded'
       this.container.classList.remove('condensed')
       this.container.classList.add('expanded')
     }
@@ -66,10 +65,16 @@ export class Panel {
 }
 
 export class EditPanel extends Panel {
-  CLASSNAME = 'right dark'
+  constructor(map) {
+    super(map)
+    this.classname = 'right dark'
+  }
 }
 
 export class FullPanel extends Panel {
-  CLASSNAME = 'full dark'
-  MODE = 'expanded'
+  constructor(map) {
+    super(map)
+    this.classname = 'full dark'
+    this.mode = 'expanded'
+  }
 }
diff --git a/umap/static/umap/js/umap.js b/umap/static/umap/js/umap.js
index 89e0d1a6..7c6d8394 100644
--- a/umap/static/umap/js/umap.js
+++ b/umap/static/umap/js/umap.js
@@ -207,13 +207,13 @@ U.Map = L.Map.extend({
       if (L.Util.queryString('share')) {
         this.share.open()
       } else if (this.options.onLoadPanel === 'databrowser') {
-        this.panel.MODE = 'expanded'
+        this.panel.mode = 'expanded'
         this.openBrowser()
       } else if (this.options.onLoadPanel === 'datalayers') {
-        this.panel.MODE = 'condensed'
+        this.panel.mode = 'condensed'
         this.openBrowser()
       } else if (this.options.onLoadPanel === 'caption') {
-        this.panel.MODE = 'condensed'
+        this.panel.mode = 'condensed'
         this.displayCaption()
       } else if (['facet', 'datafilters'].includes(this.options.onLoadPanel)) {
         this.openFacet()
diff --git a/umap/tests/integration/test_import.py b/umap/tests/integration/test_import.py
index 32fb378a..a50c7a1a 100644
--- a/umap/tests/integration/test_import.py
+++ b/umap/tests/integration/test_import.py
@@ -1,7 +1,7 @@
 import json
 import re
-from time import sleep
 from pathlib import Path
+from time import sleep
 
 import pytest
 from playwright.sync_api import expect