fixes #79068

src/vs/base/browser/ui/sash/sash.ts

@@ -179,27 +179,8 @@ export class Sash extends Disposable {
 
 		let isMultisashResize = false;
 
-		if (this.linkedSash && !(e as any).__linkedSashEvent) {
-			(e as any).__linkedSashEvent = true;
-			this.linkedSash.onMouseDown(e);
-		}
-
 		if (!(e as any).__orthogonalSashEvent) {
-			let orthogonalSash: Sash | undefined;
-
-			if (this.orientation === Orientation.VERTICAL) {
-				if (e.offsetY <= 4) {
-					orthogonalSash = this.orthogonalStartSash;
-				} else if (e.offsetY >= this.el.clientHeight - 4) {
-					orthogonalSash = this.orthogonalEndSash;
-				}
-			} else {
-				if (e.offsetX <= 4) {
-					orthogonalSash = this.orthogonalStartSash;
-				} else if (e.offsetX >= this.el.clientWidth - 4) {
-					orthogonalSash = this.orthogonalEndSash;
-				}
-			}
+			const orthogonalSash = this.getOrthogonalSash(e);
 
 			if (orthogonalSash) {
 				isMultisashResize = true;
@@ -208,6 +189,11 @@ export class Sash extends Disposable {
 			}
 		}
 
+		if (this.linkedSash && !(e as any).__linkedSashEvent) {
+			(e as any).__linkedSashEvent = true;
+			this.linkedSash.onMouseDown(e);
+		}
+
 		if (!this.state) {
 			return;
 		}
@@ -295,7 +281,17 @@ export class Sash extends Disposable {
 		domEvent(window, 'mouseup')(onMouseUp, null, disposables);
 	}
 
-	private onMouseDoubleClick(event: MouseEvent): void {
+	private onMouseDoubleClick(e: MouseEvent): void {
+		const orthogonalSash = this.getOrthogonalSash(e);
+
+		if (orthogonalSash) {
+			orthogonalSash._onDidReset.fire();
+		}
+
+		if (this.linkedSash) {
+			this.linkedSash._onDidReset.fire();
+		}
+
 		this._onDidReset.fire();
 	}
 
@@ -386,6 +382,24 @@ export class Sash extends Disposable {
 		toggleClass(this.el, 'orthogonal-end', state !== SashState.Disabled);
 	}
 
+	private getOrthogonalSash(e: MouseEvent): Sash | undefined {
+		if (this.orientation === Orientation.VERTICAL) {
+			if (e.offsetY <= 4) {
+				return this.orthogonalStartSash;
+			} else if (e.offsetY >= this.el.clientHeight - 4) {
+				return this.orthogonalEndSash;
+			}
+		} else {
+			if (e.offsetX <= 4) {
+				return this.orthogonalStartSash;
+			} else if (e.offsetX >= this.el.clientWidth - 4) {
+				return this.orthogonalEndSash;
+			}
+		}
+
+		return undefined;
+	}
+
 	dispose(): void {
 		super.dispose();