diff --git a/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx b/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx
index 1e63e4bc..1662a195 100644
--- a/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx
+++ b/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx
@@ -314,8 +314,8 @@ export class ArduinoFrontendContribution implements FrontendApplicationContribut
     protected async openSketchFiles(uri: URI): Promise<void> {
         try {
             const sketch = await this.sketchService.loadSketch(uri.toString());
-            const { mainFileUri, otherSketchFileUris, additionalFileUris } = sketch;
-            for (const uri of [mainFileUri, ...otherSketchFileUris, ...additionalFileUris]) {
+            const { mainFileUri, rootFolderFileUris } = sketch;
+            for (const uri of [mainFileUri, ...rootFolderFileUris]) {
                 await this.ensureOpened(uri);
             }
             await this.ensureOpened(mainFileUri, true);
diff --git a/arduino-ide-extension/src/browser/contributions/sketch-control.ts b/arduino-ide-extension/src/browser/contributions/sketch-control.ts
index f7d0fcb0..6e4010ce 100644
--- a/arduino-ide-extension/src/browser/contributions/sketch-control.ts
+++ b/arduino-ide-extension/src/browser/contributions/sketch-control.ts
@@ -40,8 +40,8 @@ export class SketchControl extends SketchContribution {
                     return;
                 }
 
-                const { mainFileUri, otherSketchFileUris, additionalFileUris } = await this.sketchService.loadSketch(sketch.uri);
-                const uris = [mainFileUri, ...otherSketchFileUris, ...additionalFileUris];
+                const { mainFileUri, rootFolderFileUris } = await this.sketchService.loadSketch(sketch.uri);
+                const uris = [mainFileUri, ...rootFolderFileUris];
                 for (let i = 0; i < uris.length; i++) {
                     const uri = new URI(uris[i]);
                     const command = { id: `arduino-focus-file--${uri.toString()}` };
diff --git a/arduino-ide-extension/src/common/protocol/sketches-service.ts b/arduino-ide-extension/src/common/protocol/sketches-service.ts
index de79ccf0..cf619800 100644
--- a/arduino-ide-extension/src/common/protocol/sketches-service.ts
+++ b/arduino-ide-extension/src/common/protocol/sketches-service.ts
@@ -71,6 +71,7 @@ export interface Sketch {
     readonly mainFileUri: string; // `MainFile`
     readonly otherSketchFileUris: string[]; // `OtherSketchFiles`
     readonly additionalFileUris: string[]; // `AdditionalFiles`
+    readonly rootFolderFileUris: string[]; // `RootFolderFiles` (does not include the main sketch file)
 }
 export namespace Sketch {
     export function is(arg: any): arg is Sketch {
diff --git a/arduino-ide-extension/src/node/sketches-service-impl.ts b/arduino-ide-extension/src/node/sketches-service-impl.ts
index 6183ef4f..48354cc2 100644
--- a/arduino-ide-extension/src/node/sketches-service-impl.ts
+++ b/arduino-ide-extension/src/node/sketches-service-impl.ts
@@ -94,6 +94,7 @@ export class SketchesServiceImpl implements SketchesService {
                     mainFileUri: FileUri.create(resp.getMainFile()).toString(),
                     otherSketchFileUris: resp.getOtherSketchFilesList().map(p => FileUri.create(p).toString()),
                     additionalFileUris: resp.getAdditionalFilesList().map(p => FileUri.create(p).toString()),
+                    rootFolderFileUris: resp.getRootFolderFilesList().map(p => FileUri.create(p).toString()),
                     mtimeMs
                 });
             });