For a more robust solution, JDownloader is a powerful open-source manager. By copying the Trahkino page URL, JDownloader can often parse the site to find the raw video file for you to save.
Since Trahkino uses standard web video players, you can use general-purpose video downloading tools that work across most streaming platforms.
Open the specific video page you want to save.
You usually need to start the video for at least a few seconds so the extension can detect the active media stream.
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