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Firefox unwanted downloads and bandwidth use

  • 9 replies
  • 17 have this problem
  • 1 view
  • Last reply by p.s.y.c.h.o

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Since monday I started having some issues with bandwidth, I noticed that if I start watching a video on Youtube and then go to another page (from the same window or tab) the download doesn't stop (I use a network meter from Rainmeter all the time that allowed me to notice), and most of the time it uses something around 1MB/s, it only stops if I close Firefox. So there is something wrong here, if I left the Youtube page, then the video is not playing anymore and no download should be required. I tried other Flash-based video websites like LiveLeak, but everything was fine.

I already ran scans searching for viruses, malwares, rootkits and such, nothing dangerous was found. I updated some software like Firefox itself, Java, Flash, Shockwave and antivirus before running the scans.

Since monday I started having some issues with bandwidth, I noticed that if I start watching a video on Youtube and then go to another page (from the same window or tab) the download doesn't stop (I use a network meter from Rainmeter all the time that allowed me to notice), and most of the time it uses something around 1MB/s, it only stops if I close Firefox. So there is something wrong here, if I left the Youtube page, then the video is not playing anymore and no download should be required. I tried other Flash-based video websites like LiveLeak, but everything was fine. I already ran scans searching for viruses, malwares, rootkits and such, nothing dangerous was found. I updated some software like Firefox itself, Java, Flash, Shockwave and antivirus before running the scans.

All Replies (9)

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Scan for malware with multiple programs

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.


Further information can be found in the Troubleshoot Firefox issues caused by malware article.

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Nothing found on ESET scan, TDSSKiller, MalwareBytes and MS Safety Scan. Hitman found some cookies that have been removed.

I already use Avast as permanent antivirus.

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When you close a tab, Firefox keeps that page in memory as part of the session restore feature so you can undo the tab closure. This might explain why even though it is not visible, the download keeps running in the background. I'm not sure there is a good way to communicate to Firefox that you want it to stop playing AND stop buffering a video. Hopefully someone else will have a good suggestion for that.

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If that is true, why it didn't happen before? I don't think that's the issue, there is no logic, if I stop seeing a video by closing the tab or going to other page the download needs to stop, because is clear that the user (in this case, me) doesn't want to stay there, simple.

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And it only happens with Youtube videos, even when I'm not on the webpage itself, if the website I'm looking has a youtube video, the download gets going.

When looking at some solution I saw topics regarding the Avast WebShield, is there a way to exclude Youtube from the scans?

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at p.s.y.c.h.o

I have exactly the same problem as you have right now. Have you find the culrpit yet? I'm still figuring out mine. it started 3 days ago... :(

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I have the same problem, disabling NoScript seems to stop it. Resetting profile didn't help.

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thanks for your reply droo123. Mine got fixed when disabling Flashgot.

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Well, I did the following:

FlashGot > Options > Downloads > uncheck "autostart downloads"

Then NoScript > Options > Advanced > ABE > uncheck "Enable ABE"

restarted FF, went to YT, loaded some videos for about 5 minutes, then closed all tabs, bandwidth usage went to 0