diff --git a/src/main/views/pluginsPopUps.test.js b/src/main/views/pluginsPopUps.test.js
index 67472b58..ecdce600 100644
--- a/src/main/views/pluginsPopUps.test.js
+++ b/src/main/views/pluginsPopUps.test.js
@@ -9,6 +9,8 @@ import ViewManager from 'main/views/viewManager';
 
 import PluginsPopUpsManager from './pluginsPopUps';
 
+import allowProtocolDialog from '../allowProtocolDialog';
+
 jest.mock('electron', () => ({
     shell: {
         openExternal: jest.fn(),
@@ -41,6 +43,10 @@ jest.mock('../contextMenu', () => {
     });
 });
 
+jest.mock('../allowProtocolDialog', () => ({
+    handleDialogEvent: jest.fn(),
+}));
+
 describe('PluginsPopUpsManager', () => {
     afterEach(() => {
         jest.resetAllMocks();
@@ -121,6 +127,11 @@ describe('PluginsPopUpsManager', () => {
         expect(ServerViewState.switchServer).toHaveBeenCalledWith(4545);
         expect(ViewManager.handleDeepLink).toHaveBeenCalledWith(parseURL('http://localhost:8065/team/channel'));
 
+        // Verify opening custom protocols is handled through allowProtocolDialog
+        expect(handlers['window-open']({url: 'custom:somelink'})).toEqual({action: 'deny'});
+        expect(allowProtocolDialog.handleDialogEvent).toBeCalledWith('custom:', 'custom:somelink');
+        expect(shell.openExternal).not.toHaveBeenCalledWith('custom:somelink');
+
         // Verify opening external links is allowed through browser
         expect(handlers['window-open']({url: 'https://www.example.com'})).toEqual({action: 'deny'});
         expect(shell.openExternal).toHaveBeenCalledWith('https://www.example.com');
diff --git a/src/main/views/pluginsPopUps.ts b/src/main/views/pluginsPopUps.ts
index 97ec1bbd..d9d53620 100644
--- a/src/main/views/pluginsPopUps.ts
+++ b/src/main/views/pluginsPopUps.ts
@@ -17,9 +17,11 @@ import {
 } from 'common/utils/url';
 import ContextMenu from 'main/contextMenu';
 import ViewManager from 'main/views/viewManager';
-import {generateHandleConsoleMessage} from 'main/views/webContentEventsCommon';
+import {generateHandleConsoleMessage, isCustomProtocol} from 'main/views/webContentEventsCommon';
 import MainWindow from 'main/windows/mainWindow';
 
+import allowProtocolDialog from '../allowProtocolDialog';
+
 const log = new Logger('PluginsPopUpsManager');
 
 type PluginPopUp = {
@@ -76,8 +78,14 @@ export class PluginsPopUpsManager {
 
             const serverView = ViewManager.getViewByWebContentsId(parentId)?.view;
 
+            // Check for custom protocol
+            if (isCustomProtocol(parsedURL)) {
+                allowProtocolDialog.handleDialogEvent(parsedURL.protocol, url);
+                return {action: 'deny'};
+            }
+
             // We allow internal (i.e., same server) links to be routed as expected.
-            if (serverView && parsedURL && isTeamUrl(serverView.server.url, parsedURL, true)) {
+            if (serverView && isTeamUrl(serverView.server.url, parsedURL, true)) {
                 ServerViewState.switchServer(serverView.server.id);
                 MainWindow.get()?.focus();
                 ViewManager.handleDeepLink(parsedURL);
diff --git a/src/main/views/webContentEvents.ts b/src/main/views/webContentEvents.ts
index 8aa52b7f..30144010 100644
--- a/src/main/views/webContentEvents.ts
+++ b/src/main/views/webContentEvents.ts
@@ -31,9 +31,8 @@ import ViewManager from 'main/views/viewManager';
 import CallsWidgetWindow from 'main/windows/callsWidgetWindow';
 import MainWindow from 'main/windows/mainWindow';
 
-import {generateHandleConsoleMessage} from './webContentEventsCommon';
+import {generateHandleConsoleMessage, isCustomProtocol} from './webContentEventsCommon';
 
-import {protocols} from '../../../electron-builder.json';
 import allowProtocolDialog from '../allowProtocolDialog';
 import {composeUserAgent} from '../utils';
 
@@ -42,7 +41,6 @@ type CustomLogin = {
 }
 
 const log = new Logger('WebContentsEventManager');
-const scheme = protocols && protocols[0] && protocols[0].schemes && protocols[0].schemes[0];
 
 export class WebContentsEventManager {
     customLogins: Record<number, CustomLogin>;
@@ -169,7 +167,7 @@ export class WebContentsEventManager {
             }
 
             // Check for custom protocol
-            if (parsedURL.protocol !== 'http:' && parsedURL.protocol !== 'https:' && parsedURL.protocol !== `${scheme}:`) {
+            if (isCustomProtocol(parsedURL)) {
                 allowProtocolDialog.handleDialogEvent(parsedURL.protocol, details.url);
                 return {action: 'deny'};
             }
diff --git a/src/main/views/webContentEventsCommon.ts b/src/main/views/webContentEventsCommon.ts
index 13f2e404..894b77bc 100644
--- a/src/main/views/webContentEventsCommon.ts
+++ b/src/main/views/webContentEventsCommon.ts
@@ -7,6 +7,8 @@ import type {Event} from 'electron';
 import type {Logger} from 'common/log';
 import {getLevel} from 'common/log';
 
+import {protocols} from '../../../electron-builder.json';
+
 enum ConsoleMessageLevel {
     Verbose,
     Info,
@@ -34,3 +36,8 @@ export const generateHandleConsoleMessage = (log: Logger) => (_: Event, level: n
 
     logFn(...entries);
 };
+
+export function isCustomProtocol(url: URL) {
+    const scheme = protocols && protocols[0] && protocols[0].schemes && protocols[0].schemes[0];
+    return url.protocol !== 'http:' && url.protocol !== 'https:' && url.protocol !== `${scheme}:`;
+}