Desktop support (#4484)

* Remove home link on desktop app

* Spellcheck, installation toasts, background styling, …

* Add email,slack, auth support

* More desktop style tweaks

* Move redirect to client

* cleanup

* Record desktop usage

* docs

* fix: Selection state in search input when double clicking header

app/utils/Desktop.ts

@@ -0,0 +1,36 @@
+import { isMac, isWindows } from "./browser";
+
+export default class Desktop {
+  /**
+   * Returns true if the client has inset/floating window controls.
+   */
+  static hasInsetTitlebar() {
+    return this.isMacApp();
+  }
+
+  /**
+   * Returns true if the client is running in the macOS app.
+   */
+  static isMacApp() {
+    return this.isElectron() && isMac();
+  }
+
+  /**
+   * Returns true if the client is running in the Windows app.
+   */
+  static isWindowsApp() {
+    return this.isElectron() && isWindows();
+  }
+
+  /**
+   * Returns true if the client is running in a desktop app.
+   */
+  static isElectron() {
+    return navigator?.userAgent?.includes("Electron");
+  }
+
+  /**
+   * The bridge provides secure access to API's in desktop wrapper.
+   */
+  static bridge = window.DesktopBridge;
+}