googled it, This tab's content is being shared came up but wasnt answered publicly.
Im on YouTube and out of nowhere the blue square comes up and tells me “This tabs content is being shared”.. Shared where? To who? Is it just a visual glitch? Im not sharing nor never pressed share, Idk how to share. I dont have discord. I dont have any apps that I could share with.
Image of tab sharing
The icon you’re seeing – as it’s description implies – denotes that the video being played is being shared in some way. This will appear if the content is, for example, being cast to another device.
There was an issue on macOS some time ago that affected Chromium-based browsers where this sharing icon would appear even though the content wasn’t being shared. However, that issue was fixed quite a long time ago.
Can you please tell me what OS and Brave version you’re using at this time? Additionally, to me, this looks like it may be related to an extension you have installed in the browser – can you please confirm what/which extensions you’ve installed, if any?
I get that its supposed to say im sharing my screen but im not, whatsoever.
Only 1 extension is installed, “Volume Master”. Its a volume booster.
Im on Windows 11, not MacOS. The Brave version is 1.86.142
Sorry if this comes off a little passive aggressive i’m just worried somehow im sharing to somewhere that isnt in my house, but to a neighbors next door.
@Colm,
Can you please disable the volume booster extension and test again to see if the icon appears? Additionally, if you click on the media icon in the browser toolbar (looks like a musical note), does it show that youtube is casting, as shown below?
Lastly, does this behavior occur every time you watch content on Youtube? Or is this intermittent?
Once I removed the extension the casting blue square went away! Before I did that, I checked the area you showed me, and it did not say “stop casting” like your image did. It happens intermittently but only on youtube! I fell asleep watching YT and when I woke up it was just showing the blue square, but this isnt the first or second time its happened. (didnt fall asleep on my keyboard) I think its an issue with that extension. Thank you for the help! You solved my questions and helped! 
You’re very welcome.
@Colm the answer is yes, it was the extension. Chromium browsers just add that icon so you’re aware that things are being shared, just in case it’s not intentional. As you mentioned, volume booster extensions would indeed be part of that. You can even see talk of it 8 years ago at https://www.reddit.com/r/chrome/comments/78dwaf/are_there_any_volume_booster_extensions_that_dont/
One of the people who responded claimed to be a developer for one of the extensions. Their explanation was:
This blue rectangle icon on the right of tab with title “This tab’s content is being shared.” reflects the fact that audio from that given tab is shared/passed to the chrome extension where it’s amplified and directed to the original output. It’s also visible when casting content to an external screen:
And elsewhere was explained:
I believe that happens with any extension that uses
chrome.tabCapture, which this extension needs in order to be able to actually manipulate the audio.
Anyway, I just wanted to pass along the extra little tidbit for you or whoever else might see the topic. From there, you just have to decide if you want to trust it or treat it like too much of a risk since no guarantees it’s not “spying on you” so to speak.
I’m glad that Mattches was able to guide you to a solution.
