added info how to deal with yt channels

apps/yt-dlp.md

@@ -20,4 +20,9 @@ curl -fsSL "https://dl.deno.land/release/$(curl -fsSL https://dl.deno.land/relea
 ### Use
 ```
 ./yt-dlp --js-runtimes deno:./deno 
+```
+
+## Get from youtube channel page all playlists using firefox console
+```
+Array.from(document.querySelectorAll(  "ytd-grid-playlist-renderer.style-scope > div:nth-child(2) > h3:nth-child(1) > a:nth-child(1)")).map(el => el.href).join("\n");copy(out);
 ```