Everyone default seems to be gnome nowadays, I don't understand why. One of the main reason for me to stick with Ubuntu was unity being a great DE.

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Web Browser: Firefox

Email Client: ???

Terminal: Gnome terminal

IDE: VIM + plugins, Visual Studio Code

File manager: 16.0 default

Basic Text Editor: VIM

IRC/Messaging Client: ???

PDF Reader: 16.04 default

Office Suite: LibreOffice, markdown + pandoc -> pdf

Calendar: ???

Video Player: VLC

Music Player: ???

Photo Viewer: ???

Screen recording: Simple Screen Recorder

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