Revert "Browser: Remove duplicate border in Modern UI"

src/vs/workbench/contrib/browserView/electron-browser/features/webContentsViewRendererFeature.ts

@@ -14,51 +14,17 @@ import { ILogService } from '../../../../../platform/log/common/log.js';
 import {
 	IBrowserViewKeyDownEvent,
 } from '../../../../../platform/browserView/common/browserView.js';
-import { BrowserViewSharingState, IBrowserViewModel } from '../../common/browserView.js';
+import { IBrowserViewModel } from '../../common/browserView.js';
 import {
 	BrowserEditor,
 	BrowserEditorContribution,
 	BrowserWidgetLocation,
 	IBrowserEditorWidget,
 	IContainerLayout,
-	IContainerLayoutPane,
 	IContainerLayoutOverride,
 } from '../browserEditor.js';
 import { BrowserOverlayManager, BrowserOverlayType } from '../overlayManager.js';
 
-const BROWSER_CONTAINER_BORDER_PADDING = 3;
-
-/**
- * Returns room for the browser page border unless the Modern UI editor card already supplies the resting boundary.
- */
-export function getBrowserContainerPadding(browserContainer: HTMLElement, isShared: boolean, hasDeviceEmulation: boolean): { top: number; right: number; bottom: number; left: number } {
-	const editorPart = browserContainer.closest('.part.editor');
-	const hasModernUIEditorCard = !!editorPart
-		&& !editorPart.classList.contains('modal-editor-part')
-		&& !!editorPart.closest('.monaco-workbench.modern-ui');
-	const padding = hasModernUIEditorCard && !isShared && !hasDeviceEmulation ? 0 : BROWSER_CONTAINER_BORDER_PADDING;
-	return { top: padding, right: padding, bottom: padding, left: padding };
-}
-
-/**
- * Snaps Browser bounds to host pixels, covering the available area when the editor card owns its boundary.
- */
-export function snapBrowserContainerLayout(current: IContainerLayout, pane: IContainerLayoutPane, zoomFactor: number, coverAvailableArea: boolean): IContainerLayout {
-	const snapDown = (value: number) => Math.floor(value * zoomFactor) / zoomFactor;
-	const snapUp = (value: number) => Math.ceil(value * zoomFactor) / zoomFactor;
-	const absoluteLeft = pane.originX + (current.left ?? 0);
-	const absoluteTop = pane.originY + (current.top ?? 0);
-	const snappedAbsoluteLeft = snapDown(absoluteLeft);
-	const snappedAbsoluteTop = snapDown(absoluteTop);
-	return {
-		...current,
-		width: coverAvailableArea && current.width !== 0 ? snapUp(absoluteLeft + current.width) - snappedAbsoluteLeft : snapDown(current.width),
-		height: coverAvailableArea && current.height !== 0 ? snapUp(absoluteTop + current.height) - snappedAbsoluteTop : snapDown(current.height),
-		left: snappedAbsoluteLeft - pane.originX,
-		top: snappedAbsoluteTop - pane.originY,
-	};
-}
-
 /**
  * Default browser renderer: drives a Chromium WebContentsView.
  *
@@ -122,16 +88,31 @@ class WebContentsViewRendererFeature extends BrowserEditorContribution {
 	}
 
 	override beforeContainerLayout(): IContainerLayoutOverride {
-		const padding = getBrowserContainerPadding(
-			this.editor.browserContainer,
-			this._model?.sharingState === BrowserViewSharingState.Shared,
-			!!this._model?.device,
-		);
-		const usesModernUIEditorCardBoundary = padding.top === 0;
-
 		return {
-			padding,
-			compute: (current, pane): IContainerLayout => snapBrowserContainerLayout(current, pane, getZoomFactor(this.editor.window), usesModernUIEditorCardBoundary),
+			padding: { top: 3, right: 3, bottom: 3, left: 3 },
+
+			// Snap CSS-pixel values down so `v × hostZoom` is an exact integer:
+			// main places the WCV at `round(v × hostZoom) × systemDPR` physical
+			// pixels while CSS renders it at `v × hostZoom × systemDPR`, so this
+			// collapses main's rounding to a no-op and keeps the WebContentsView
+			// aligned with the placeholder screenshot. We snap the absolute
+			// origin (pane origin + local offset) then derive the corresponding
+			// local position so the DOM element and the WCV land on the same
+			// physical pixel. Runs late so it refines whatever sizing upstream
+			// contributions (e.g. device emulation) produced.
+			compute: (current, pane): IContainerLayout => {
+				const z = getZoomFactor(this.editor.window);
+				const snap = (v: number) => Math.floor(v * z) / z;
+				const absLeft = pane.originX + (current.left ?? 0);
+				const absTop = pane.originY + (current.top ?? 0);
+				return {
+					...current,
+					width: snap(current.width),
+					height: snap(current.height),
+					left: snap(absLeft) - pane.originX,
+					top: snap(absTop) - pane.originY,
+				};
+			},
 			priority: 1000,
 		};
 	}
@@ -202,7 +183,6 @@ class WebContentsViewRendererFeature extends BrowserEditorContribution {
 		store.add(model.onDidKeyCommand(keyEvent => void this._handleKeyEvent(keyEvent)));
 		store.add(model.onDidNavigate(() => this._refresh(true)));
 		store.add(model.onDidChangeLoadingState(() => this._refresh(true)));
-		store.add(model.onDidChangeSharingState(() => this.editor.layoutBrowserContainer()));
 
 		this._refresh();
 		void this._doScreenshot();