Web development question

[Carrot]

I'm wondering how something is coded, I haven't done web development in ages.

I don't have push notifications enabled, this is unrelated to push notifications. I'm wondering how it works without them.

Let's say I have 3 tabs of SaSu opened:
Topic 1 (tab1)
Topic 2 (tab2)
Topic 3 (tab3)

I can leave those tabs open for hours, days, nothing changes.

Then I go to Tab 1 and react to a message. Or refresh the page. During those hours people might have reacted to my messages, so the titles of those pages will change to something like this:

(4) Topic 1 (tab1)
(4) Topic 2 (tab2)
(4) Topic 3 (tab3)

Meaning I have 4 new notifications. When reacting to a message, I probably get some response with additional information about the notifications, full refresh is even more obvious.

I understand why the title of tab 1 changes, I interacted with that tab. But how do the other two tabs know how to change the title, how do the other two tabs know about the new notifications?

Web is incredibly sandboxed and sites don't have complete information about the users computer and shouldn't know about about other tabs the user has opened. Maybe something changed in last 10 years or so, maybe the web developer has information about other opened tabs within the same domian, through javascript or something?

I don't need this for anything, just curious.

 

[Lyn]

I'm wondering how something is coded, I haven't done web development in ages.

I don't have push notifications enabled, this is unrelated to push notifications. I'm wondering how it works without them.

Let's say I have 3 tabs of SaSu opened:
Topic 1 (tab1)
Topic 2 (tab2)
Topic 3 (tab3)

I can leave those tabs open for hours, days, nothing changes.

Then I go to Tab 1 and react to a message. Or refresh the page. During those hours people might have reacted to my messages, so the titles of those pages will change to something like this:

(4) Topic 1 (tab1)
(4) Topic 2 (tab2)
(4) Topic 3 (tab3)

Meaning I have 4 new notifications. When reacting to a message, I probably get some response with additional information about the notifications, full refresh is even more obvious.

I understand why the title of tab 1 changes, I interacted with that tab. But how do the other two tabs know how to change the title, how do the other two tabs know about the new notifications?

Web is incredibly sandboxed and sites don't have complete information about the users computer and shouldn't know about about other tabs the user has opened. Maybe something changed in last 10 years or so, maybe the web developer has information about other opened tabs within the same domian, through javascript or something?

I don't need this for anything, just curious.

I'm not sure, I'm a self-taught newbie, but I think it has something to do with the features like localStorage or BroadcastChannel API that the browser provides, and the website just uses them with JavaScript.

It's like one tab writes something in that storage, and other tabs from the same domain can notice the change and react to it.

But I doubt that web developers explicitly receive info about users' opened tabs.

But that's just my guess, maybe someone more knowledgeable will prove me wrong

 

[Carrot]

Thank you, that makes a lot of sense. Or cookies. Anything that one tab can write to, and others can read without sending a request.

Seems obvious now that you mentioned it.

 

[Hvergelmir]

BroadcastChannel API

This sounds accurate. (Got curious myself.)
https://developer.mozilla.org/en-US/docs/Web/API/Broadcast_Channel_API

 

[nobodycaresaboutme]

BroadcastChannel API

I am a self-taught developer too. I didn't know this API. Thank you for enlightening me!