Allow cmr+r reload from webview developer tools

Fixes #48975

src/vs/workbench/parts/webview/electron-browser/webview-pre.js

@@ -34,6 +34,7 @@
 	var loadTimeout;
 	var pendingMessages = [];
 	var enableWrappedPostMessage = false;
+	let isInDevelopmentMode = false;
 
 	const initData = {
 		initialScrollProgress: undefined
@@ -89,7 +90,6 @@
 	};
 
 	const onMessage = (message) => {
-		// Old school webview. Forward exact message
 		ipcRenderer.sendToHost(message.data.command, message.data.data);
 	};
 
@@ -322,6 +322,12 @@
 			// write new content onto iframe
 			newFrame.contentDocument.open('text/html', 'replace');
 			newFrame.contentWindow.onbeforeunload = () => {
+				if (isInDevelopmentMode) { // Allow reloads while developing a webview
+					ipcRenderer.sendToHost('do-reload');
+					return false;
+				}
+
+				// Block navigation when not in development mode
 				console.log('prevented webview navigation');
 				return false;
 			};
@@ -395,6 +401,10 @@
 			initData.initialScrollProgress = progress;
 		});
 
+		ipcRenderer.on('devtools-opened', () => {
+			isInDevelopmentMode = true;
+		});
+
 		// Forward messages from the embedded iframe
 		window.onmessage = onMessage;
 

src/vs/workbench/parts/webview/electron-browser/webviewElement.ts

@@ -158,6 +158,10 @@ export class WebviewElement {
 							this._onDidScroll.fire({ scrollYPercentage: event.args[0] });
 						}
 						return;
+
+					case 'do-reload':
+						this.reload();
+						return;
 				}
 			}),
 			addDisposableListener(this._webview, 'focus', () => {
@@ -169,7 +173,10 @@ export class WebviewElement {
 				if (this._contextKey) {
 					this._contextKey.reset();
 				}
-			})
+			}),
+			addDisposableListener(this._webview, 'devtools-opened', () => {
+				this._send('devtools-opened');
+			}),
 		);
 
 		this._webviewFindWidget = new WebviewFindWidget(this._contextViewService, this);