Instantbird is a cross-platform instant messaging client based on Mozillas XULRunner and the open source library libpurple used in Pidgin. Developed by Florian Quèze and Quentin Castier
License: Open Source
Instantbird is a lightweight and straightforward messaging client primarily focused on speed and ease of use, while Kopete offers more robust features and integration with the KDE environment but can be heavier on resources. Users looking for simplicity may prefer Instantbird, whereas those needing advanced functionality might lean towards Kopete.