Steps:

Playlist Editor > Right-click > Playlist Context Menu > Select "Create New Playlist With Selected Items":

Produces the desired playlist in a new tab named "Untitled-0.m3u8", "Untitled-1.m3u8", etc.

but:

1. The file format of the playlist in the editor — the one from which the new playlist file is produced, — is M3U. One would expect the same extension to apply to the newly created playlist by default?

2. To save the new playlist by clicking on the Save button, i.e. the diskette icon on the toolbar, produces an unidentifiable flash of "something" on the screen. It does not produce the expected Save Dialogue box, which usually contains the various saving options such as, for example, the preferred name, the location, nor the desired file extension.

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