In 2018, it was possible to wind up using the "Charles" program.
But the method is no longer active.
We will act differently, but no less effectively!

First you need to have a YouTube account, you also need to find any video that will be massively uploaded to your channel.
I made a video of just 5 seconds of black screen.
Having 1 video, copy ctrl + c and press ctrl + v to create a copy of the video (youtube does not upload video replays).
You can upload up to 10 videos per day to YouTube (if you pass verification, then significantly more).
There is no point in having more than 100 videos, and less than 100 consumes unnecessary body movements.

Having 10-100 videos on the channel, we connected YouTube to Steam.

To avoid selecting each video manually, let's paste the code into the browser console (F12) instead:

document.querySelectorAll('input.vid_cb[name="videos[]"]').forEach(cb => { if (!cb.checked) { cb.click()}})

Or with this code (it removes browser debug logs and shows how many videos were clicked, but the work delay is 1 sec):

(()=>{let c=0, boxes=[...document.querySelectorAll('input.vid_cb[name="videos[]"]')].filter(cb=>!cb.checked);let clickNext=()=>{let cb=boxes.shift();if(cb){cb.click();c++;requestAnimationFrame(clickNext)}else console.log(`👆 Clicked ${c} video`)};requestAnimationFrame(clickNext);return '⌛ Processing...'})()

Pressing Enter selects all videos (the code find all checkboxes and clicks on them)



You can add a maximum of 1k video to Steam, then you need to wait 40 minutes (this is due to Steam Cloud restrictions, so do not upload screenshots... at the same time), the video is loaded only if there is a inscription (it does not always appear, this will mean the limit has been reached):