This must have been asked, apologies for asking again.
I’m running Firefox, and the “SD” icon in browser tabs will often have a ‘1’ superimposed. It also often does not. I think a single time I have seen a ‘2’ on top of the ‘SD’.
What’s this all about?
I don’t know the answer, but I’m going to piggyback my own question.
Similar to you, I see a number that changes sometimes, either 1 or a 2, when SD is part of a “search suggestions” in my browser.
Of course this doesn’t happen all the time. Tonight is one of those times with no number.
I think it must be related to your question Sqeegee
And just now this own thread’s number changed from blank to 2.
hmmm maybe cause there are two of us currently posting right now?
Number of replies?
¯_(ツ)_/¯
Is it the number of notifications you have?
Nope. I have 1 notification (yours for answering my thread) and the browser tab has a ‘2’ for this thread. Maybe the number of people viewing a thread? I’ve seen some pretty active threads just have a 1 on them though. 
I don’t see it in either Safari or Firefox, so I wonder if it’s some add-on you have.
FF Windows or Mac?
Mac OS X
I just clickity-clicked a bunch of threads on my work Mac and haven’t gotten the number over the SD, vs the personal Win box I started the thread on. So maybe it’s platform specific? OTOH, the number appears only sometimes. I have 6 SDMB Win FF tabs open at the moment, none are tagged with a number. It comes and goes.
I have nothing special installed in my FireFox. Ad Blocker Ultimate and LastPass. I think the numbers come from SDMB.
I have it, too. It said 15 in the tab, and my notifications said 14. When I clicked on the notifications, both numbers reset.
Yes, it’s the number of notifications.
But it doesn’t always update when you look at the notifications unless you refresh the page.
This is also a configurable feature. If someone is not seeing it, that’s probably because they didn’t opt into it.
From your user control panel page, select Preferences from the top menu then Interface from the left side menu. Then scroll down to the Other section.
Near the bottom are two items: a checkbox for “Show counts on browser icon” and a dropdown for what to show the count of on the browser tab.
If you do play with it, don’t forget to click the [Save Changes] and refresh the page of interest to see the effect.
OK, asked and answered - thanks guys!
Thanks for pointing out the setting. I just turned it off. What a weird useless feature, since you also see the number of notifications over your user icon on every page.
This is what i believe, too
FWIW …
I read the Dope by opening 15 or 20 tabs quickly off the “unread” or “latest” page, then reading and replying to those tabs over the next hour or so. I often see the numbers appear and change on tabs I opened 20 minutes ago that I have neither viewed nor refreshed since.
My experience to date is the little numbers for messages and notifications that overlay my user icon at the upper right of each page are set when that page loads and are not updated as stuff changes in the background.
I admit I haven’t tried all the combinations of those two settings long enough to sort out exactly what each of them does and how or even whether they interact with each other.
Agree the user icon number display is not completely reliable; it seems to update accurately on the page you’re reading, and may not update if you have a bunch of tabs open on every open tab.
FYI, if you turn off the “Show counts on browser icon” preference, the browser tab instead shows “(somenumber) Thread Name” in text instead, so the preference is kinda useless.
Welcome to the Straight Dope!