AudioCut
MP3/FLAC/WAV audio cutter — cutting audio files visually.
Linux
EasyPlayer
A simple video and audio player based on mpv.
VideoMerge
UI tool to merge different videos using ffmpeg.
MediaInfoGui
QT5 GUI for MediaInfo data.
YoutubeDownloader
GTK3 UI for youtube-dl.
PDFMaker
Simple PDF converter GUI for pictures, using ImageMagick.
VideoCut
MPEG2, MP4, MKV, WEBM cutter for Linux using MPV and libavcodec or ffmpeg. Cutting is lossless — the target file is not re-encoded.