feat: Support exporting with dark mode (#3046)

Co-authored-by: Lipis <lipiridis@gmail.com>
Co-authored-by: dwelle <luzar.david@gmail.com>

src/renderer/renderScene.ts

@@ -49,6 +49,7 @@ import {
 } from "../element/transformHandles";
 import { viewportCoordsToSceneCoords, supportsEmoji } from "../utils";
 import { UserIdleState } from "../excalidraw-app/collab/types";
+import { APPEARANCE_FILTER } from "../constants";
 
 const hasEmojiSupport = supportsEmoji();
 
@@ -211,6 +212,10 @@ export const renderScene = (
   const normalizedCanvasWidth = canvas.width / scale;
   const normalizedCanvasHeight = canvas.height / scale;
 
+  if (sceneState.exportWithDarkMode) {
+    context.filter = APPEARANCE_FILTER;
+  }
+
   // Paint background
   if (typeof sceneState.viewBackgroundColor === "string") {
     const hasTransparence =