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Firefox always uploading something

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Hello everyone.

I started using Firefox not long ago, to try it and see if it's better than Chrome.

But, I noticed few days ago that every time that Firefox is open (with a page loaded, or only a blank tab open), Firefox will always use the internet to download or upload something.

Like, when I'm watching a video, the Download rate is high, but there's still a little (like 2 kb or less) of upload rate. Also, even with only a blank tab open, there's still download and upload (the download rate is not so much compared to watching a video, but still). I can see here that right now, with the page already loaded, I'm still downloading and uploading something.

Anyone having this problem (or maybe a bug)?

Hello everyone. I started using Firefox not long ago, to try it and see if it's better than Chrome. But, I noticed few days ago that every time that Firefox is open (with a page loaded, or only a blank tab open), Firefox will always use the internet to download or upload something. Like, when I'm watching a video, the Download rate is high, but there's still a little (like 2 kb or less) of upload rate. Also, even with only a blank tab open, there's still download and upload (the download rate is not so much compared to watching a video, but still). I can see here that right now, with the page already loaded, I'm still downloading and uploading something. Anyone having this problem (or maybe a bug)?

All Replies (5)

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Just noticed that the amount of uploading is ~10% of the download. Example: Right now is 6MB of download and 700KB of upload.

Will still look for anything suspisious.

EDIT: Forget it. It's not really 10%, but still doing uploads.

In this case, I have here160MB of download and 6 MB of upload (while watching a video in HD).

Modified by Aya_Tachibana

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Are you sure that this isn't the normal traffic that you have with confirming received packets and possibly keep the connection alive?

Did you check the packet with Wireshark or another utility?

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cor-el said

Are you sure that this isn't the normal traffic that you have with confirming received packets and possibly keep the connection alive? Did you check the packet with Wireshark or another utility?

After using bmon for some tests, here is my results:

- When Fireforx isn't open, there's sometimes traffic, but when I start Firefox, there will be download and upload traffic. - When not using Firefox, the traffic is normally in the size of bytes (not even KB). But with Firefox, it may go higher. - I actually can't see what program is actually using the traffic, but if starting Firefox does cause some download and upload, then does have a connection with it.

EDIT: Installed nethogs to test my internet. And yes, when I start Firefox, it sends and receives some bytes.

EDIT2: Now, I even tried to disable the plugins and such, but no success. Even if the homepage is a new blank tab, there's still some networking occuring.

EDIT3: It looks like that even going into Firefox safe mode doesn't fix this. Any other ideas?

EDIT4: Ok, maybe what is happening is actually normal? Maybe is just Firefox team receiving some info about my computer?

Modified by Aya_Tachibana

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This is probably just some normal traffic between Firefox and your ISP to keep the connection alive. I see a few (less than 100) bytes being send and received as well every few seconds on Linux.

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cor-el said

This is probably just some normal traffic between Firefox and your ISP to keep the connection alive. I see a few (less than 100) bytes being send and received as well every few seconds on Linux.

Just continuing the testing here. Normally, when Firefox starts, it goes to few KBs (5 to 15), and them it keeps sending and receiving few bytes (but it sometimes goes to KBs)

Maybe it's really normal traffic. But it's just strange that I keep sending and receiving.

EDIT: Just tested again, when opening Firefox (I only have a new tab), I downloaded aprox. 40 kb and uploaded 15 kb. And even after a few minutes, it still happened to do some download/upload.

I don't think it's really just a normal traffic. Do you know what it could be?


EDIT2: Even doing a refresh didn't resolved the issue. This is becoming really annoying.

I still didn't thought about that, but it's possible that the problem is caused by a malware? Even through I'm using Linux and only visiting trusted websites, this can still happens.

EDIT3: Even thought it can be malware related, more tests made:

- Just like your Firefox, it also keeps uploading/downloading few bytes every few seconds, but it happens after uploading and downloading some KB s in a blank tab.

- Those high amounts of upload and download only happens when I start Firefox. Opening a blank tab with Firefox open just downloads and uploads few bytes (probably normal).

Anything else I can try to fix this bug?


EDIT4: Until now, I forgot to observe something. Even through the upload and download rate goes to KB/s, the duration of that rate is almost none. So, in the end, I'm downloading and uploading (every time that I open Firefox) 20kb (or 0.02 MB).

This a really small amount right? Is this amount normal?

EDIT5: Even after the last update, I still have this. I even tested in a computer at the school (Windows 7) and it had the same 20kb of upload when opening Firefox (could only test the upload, and also I don't know if that PC is actually clean of malware, etc).

Can anyone just test it and tell here if this is normal?

Forgot to say, thank you everyone who's trying to help me.


EDIT6 (Probably final): After many tests at the schools Virtual Machine running Ubuntu 12.04 LTS, I observed that in the version aprox. 20 of Firefox, the bug didn't happened.

But after updating it to the version 38, I saw that (after installing the same addons), the bug also happenned in there (with lower rate of download\upload, but still happened), so this appears to be a normal behavior of Firefox.

I really happy to know that this is probably normal, but can anyone also tests on any machine just to be sure?

Thank you guys for helping me.

Modified by Aya_Tachibana