For Datasette.app I wanted to ensure that links to external URLs would open in the system browser.
\nThis recipe works:
\nfunction postConfigure(window) {\n window.webContents.on(\"will-navigate\", function (event, reqUrl) {\n let requestedHost = new URL(reqUrl).host;\n let currentHost = new URL(window.webContents.getURL()).host;\n if (requestedHost && requestedHost != currentHost) {\n event.preventDefault();\n shell.openExternal(reqUrl);\n }\n });\n}The will-navigate event fires before any in-browser navigations, which means they can be intercepted and cancelled if necessary.
I use the URL() class to extract the .host so I can check if the host being navigated to differs from the host that the application is running against (which is probably localhost:$port).
Initially I was using require('url').URL for this but that doesn't appear to be necessary - Node.js ships with URL as a top-level class these days.
event.preventDefault() cancels the navigation and shell.openExternal(reqUrl) opens the URL using the system default browsner.
I call this function on any new window I create using new BrowserWindow - for example:
mainWindow = new BrowserWindow({\n width: 800,\n height: 600,\n show: false,\n});\nmainWindow.loadFile(\"loading.html\");\nmainWindow.once(\"ready-to-show\", () => {\n mainWindow.show();\n});\npostConfigure(mainWindow);