Advnotlab.com Will Get Ads in Your Browser
Advnotlab dot com is a simple, low-effort misleading website. The only purpose of its existence is to get intrusive and annoying advertising into the browsers of as many people as possible, generating revenue for the site owner in the process.
The page at Advnotlab dot com will display a simple clipart image of a hard drive with a green arrow over it, implying a file download. Along with this, your browser will display its default "allow notifications" dialog box.
The party operating the website didn't even bother to put some sort of text on the page to incite users to click allow, they chose to just leave the mystery download icon on the page. Allowing ads from websites similar to Advnotlab dot com will only lead to your browser starting to display a lot of annoying pop-up ads, delivered through push notifications functionality.
Some of those ads can be sourced from rogue ad networks and can expose your system to further risks if you click them, redirecting to other misleading pages or malicious sites.
Just remember that if a random domain and website needs you to allow push notifications, chances are, this is only done so that the page can send you annoying and intrusive pop-up ads, so your best bet is to simply close the page immediately when you see the prompt.