Pars Enterprise Platforms use KDE Instant Messaging Contacts as default internet messenger, There are still many other internet messengers out of box such Pidgin, Signal, Telegram and etc.
KDE IM configuration is available under Programs Menu > Settings > System Settings > Instant Messaging and VoIP > Add Account, KDE IM Contacts has a few important features such as: Multi Protocol, Messaging, VoIP System, Video Call, Conference, Desktop Widget.
Signal Messenger
Signal is a cross-platform encrypted messaging service developed by the Signal Foundation and Signal Messenger LLC. It uses the Internet to send one-to-one and group messages, which can include files, voice notes, images and videos. Its mobile apps can also make one-to-one voice and video calls.
Telegram: messaging app with a focus on speed and security, it is super-fast, simple and free. You can use Telegram on all your devices at the same time — your messages sync seamlessly across any number of your phones, tablets or computers.
Pidgin Messenger
Pidgin (formerly named Gaim) is a free and open-source multi-platform instant messaging client, based on a library named libpurple that has support for many instant messaging protocols, allowing the user to simultaneously log into various services from a single application, with a single interface for both the popular and obsolete protocols (from AOL to Discord), thus avoiding the hassle of having to deal with a new bloated, unaudited, closed-source, and different piece of software for each device and protocol. Pidgin is widely used for its Off-the-Record Messaging (OTR) plugin, which offers end-to-end encryption.
Off-the-Record Messaging (OTR) is a cryptographic protocol that provides encryption for instant messaging conversations. OTR uses a combination of AES symmetric-key algorithm with 128 bits key length, the Diffie–Hellman key exchange with 1536 bits group size, and the SHA-1 hash function. In addition to authentication and encryption, OTR provides forward secrecy and malleable encryption.
