I was cleaning my outlook.com (hotmail) inbox and I found an unread two month old email from LinkedIn, I open it up to find that the header has a badge like notification number:

Curious, I opened a new tab in Chrome to checkout my LinkedIn account, and surprise... I really have 3 new notifications from yesterday (I check it almost every day) :O

I came back to outlook, the badge continuous there, but after I reload the page the badge was gone:

And of course in LinkedIn, the notifications were gone too:

I remember see this before using my phone, but I assumed there was some kind of connection between the Mail app and the LinkedIn app. In case you wonder, I do not have the chrome extension from LinkedIn installed. Now the question... How the hell I can see this dinamic LinkedIn notification in outlook? and how can I do something similar with my work?

Thank you all in advance, hope you can guide me to achieve something similar.