A non-transitory computer-readable storage medium may comprise instructions stored thereon that, when executed by at least one processor, are configured to cause an intermediary server to at least receive, from a first client device, a first login request via a first browser installed on the first client device, the first login request identifying a user account, receive, from a third-party server, a message request, the message request including an identifier and indicating a browser application or a browser extension, map the identifier to the user account, determine whether the user account has installed the browser application or browser extension, and if the user account has installed the browser application or browser extension, send a first message to the first browser based on the message request.