link_utils: exposing whitelisted protocols to user settings

This commit exposes the whitelisted protocol list to the user
settings.json file. This allows user to extend or modify the list of
linkifiers that are directly opened by the os instead of being opened
via the redirect html method.

app/common/config-schemata.ts

@@ -36,6 +36,7 @@ export const configSchemata = {
   useManualProxy: z.boolean(),
   useProxy: z.boolean(),
   useSystemProxy: z.boolean(),
+  whitelistedProtocols: z.string().array(),
 };
 
 export const enterpriseConfigSchemata = {

app/common/link-util.ts

@@ -3,10 +3,20 @@ import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
 
+import * as ConfigUtil from "./config-util.js";
 import {html} from "./html.js";
 
+/* Fetches the current protocolLaunchers from settings.json */
+const whitelistedProtocols = ConfigUtil.getConfigItem("whitelistedProtocols", [
+  "http:",
+  "https:",
+  "mailto:",
+  "tel:",
+  "sip:",
+]);
+
 export async function openBrowser(url: URL): Promise<void> {
-  if (["http:", "https:", "mailto:"].includes(url.protocol)) {
+  if (whitelistedProtocols.includes(url.protocol)) {
     await shell.openExternal(url.href);
   } else {
     // For security, indirect links to non-whitelisted protocols