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
Miranda IM is a highly customizable, lightweight messaging client with extensive plugin support, making it ideal for advanced users. Instantbird, on the other hand, offers a user-friendly experience with cross-platform compatibility, but may not provide the same level of customization.