WebView Extensions asset load 403 Forbidden #13373 (#13382)

* fix regression where webview based editors were using the new more stable origin URL from regular web views
* add doc

packages/plugin-ext/src/plugin/custom-editors.ts

@@ -129,7 +129,7 @@ export class CustomEditorsExtImpl implements CustomEditorsExt {
         if (!entry) {
             throw new Error(`No provider found for '${viewType}'`);
         }
-        const panel = this.webviewExt.createWebviewPanel(viewType, title, {}, options, entry.plugin, handler);
+        const panel = this.webviewExt.createWebviewPanel(viewType, title, {}, options, entry.plugin, handler, false);
         const webviewOptions = WebviewImpl.toWebviewOptions(options, this.workspace, entry.plugin);
         await this.proxy.$createCustomEditorPanel(handler, title, widgetOpenerOptions, webviewOptions);
 

packages/plugin-ext/src/plugin/webviews.ts

@@ -126,19 +126,33 @@ export class WebviewsExtImpl implements WebviewsExt {
         return panel;
     }
 
+    /**
+     * Creates a new webview panel.
+     *
+     * @param viewType Identifies the type of the webview panel.
+     * @param title Title of the panel.
+     * @param showOptions Where webview panel will be reside.
+     * @param options Settings for the new panel.
+     * @param plugin The plugin contributing the webview.
+     * @param viewId The identifier of the webview instance.
+     * @param originBasedOnType true if a stable origin based on the viewType shall be used, false if the viewId should be used.
+     * @returns The new webview panel.
+     */
     createWebviewPanel(
         viewType: string,
         title: string,
         showOptions: theia.ViewColumn | theia.WebviewPanelShowOptions,
         options: theia.WebviewPanelOptions & theia.WebviewOptions,
         plugin: Plugin,
-        viewId: string
+        viewId: string,
+        originBasedOnType = true
     ): WebviewPanelImpl {
         if (!this.initData) {
             throw new Error('Webviews are not initialized');
         }
         const webviewShowOptions = toWebviewPanelShowOptions(showOptions);
-        const webview = new WebviewImpl(viewId, this.proxy, options, this.initData, this.workspace, plugin, hashValue(viewType));
+        const origin = originBasedOnType ? hashValue(viewType) : undefined;
+        const webview = new WebviewImpl(viewId, this.proxy, options, this.initData, this.workspace, plugin, origin);
         const panel = new WebviewPanelImpl(viewId, this.proxy, viewType, title, webviewShowOptions, options, webview);
         this.webviewPanels.set(viewId, panel);
         return panel;