How can i get rid of an annoying pop-up message that appears each time i use Youtube?

The explanation is that I am still using the old design of Youtube because I really dislike the newest look and it even causes me certain issues in some videos by not playing them at all, so these are the reasons of why I´ve choosen keep using the old Youtube design.

Well, the issue is that since a few weeks ago, I´ve start getting an annoying pop-up message when I visit any of the sections of the Youtube page, an annoying message asking me to swap to the new design, see this screenshot for more info:
I will not going to swap to the new YT design because it gives me issues so will stand with the old design as long as I can. Since the old design seems to keep working pretty fine (for me at least), I was looking for a method like a script/tool I could install in my web browser, so each time I use Youtube, this bloody pop-up message wiill not appear anymore.

Web browsers I use: Opera and Chrome.

This is the console element that appears when I inspect the pop-up message:


<div class="alerts-wrapper">
<div id="alerts" class="content-alignment">
<div class="yt-alert yt-alert-default yt-alert-info " id="old-browser-alert">
<div class="yt-alert-icon">
<span class="icon master-sprite yt-sprite"></span>
</div>
<div class="yt-alert-content" role="alert">
<div class="yt-alert-message" tabindex="0">
"
This design of YouTube will soon stop being available. "
<a href="/new">Change to the new design of YouTube</a>
</div>
</div>
</div><div class="yt-alert-buttons"></div></div>
</div>
</div>
</div>


Here is a screenshot from the console element:

NOTE: If this is not the correct place, anyone have a remote idea where I could get help on this subject, which forums should I use to get help with this kind of stuff?
 
Uhhh, what's a "modded" version of YouTube?
Enhancer for Youtube. Add block for Youtube. Dark/Light/Floral Themes for Youtube. It's all free, have a look~ https://lmgtfy.com/?q=enhancer+for+youtube&pp=1

  • Highly customizable and easy-to-use extension that allows you to:
    ✔ Control volume level and playback speed with the mouse wheel

    ✔ Remove ads from videos (automatically or on-demand)

    ✔ Whitelist channels to not automatically remove their ads

    ✔ Remove annotations (automatically or on-demand)

    ✔ Automatically play videos in 4K, HD, or any other preferred format

    ✔ Loop videos (in part or in whole)

    ✔ Use custom themes

    ✔ Use a larger video player

    ✔ Pin the video player

    ✔ Execute your own actions using JavaScript

    ✔ And more..
 
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