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Progressive degradation of speed unresolved by troubleshooting

  • 9 replies
  • 1 has this problem
  • 2 views
  • Last reply by Datango

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Firefox 61.0.1 Windows 10 Pro v 1803

I have been experiencing gradual degradation of performance of FF which troubleshooting has failed to resolve.

In an attempt to resolve the issue a clean install of Windows was performed and FF reinstalled.

The new profile also showed much slower speeds compared with other browsers (Less than half).

It was not possible to run FF in Safe Mode because the speed test required Adobe Flash.

Any suggestions how this issue may be resolved will be much appreciated.

Firefox 61.0.1 Windows 10 Pro v 1803 I have been experiencing gradual degradation of performance of FF which troubleshooting has failed to resolve. In an attempt to resolve the issue a clean install of Windows was performed and FF reinstalled. The new profile also showed much slower speeds compared with other browsers (Less than half). It was not possible to run FF in Safe Mode because the speed test required Adobe Flash. Any suggestions how this issue may be resolved will be much appreciated.

All Replies (9)

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Hi, your reinstall is different than ours. Please : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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Thanks for the response.

As the OS and FF have been completely clean reinstalled there should be no detritus remaining.

Nevertheless I have deleted the FF files, restarted and reinstalled and performed a Disk Cleanup and reinstalled FF but the issue persists.

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Do you use Windows Defrag ?

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Yes Windows defrag is used generally, but this is a completely new installation.

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You used the Full Version Installer ? What security Software are you running please ?

Please Copy/Paste : about:support into the Address Bar and Enter

Go down to Extensions and copy off what you are running please and paste in a reply.

Since you are running some sort of test that is not what Firefox Support is for.

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Thanks for the response.

I can confirm that a Full Version Installer was used (38,264KB file downloaded from https://www.mozilla.org/en-US/firefox/all/)

The security software currently being used is Bitdefender but was previously Avira when similar results were obtained.

All Extensions in the regular profile are disabled:

Avira Browser Safety 2.6.1.19731 false abs@avira.com Bing Search 1.0.0.6 false bingsearch.full@microsoft.com Bitdefender Wallet 21.1.10 false bdwtwe@bitdefender.com LogMeIn, Inc. Remote Access Plugin 1.0.0.608 false LogMeInClient@logmein.com Microsoft .NET Framework Assistant 1.2.1 false {20a82645-c095-46ed-80e3-08825760534b} Perplexbar 2.5.2 false perplexbar@perplexorum.com Stylish - Custom themes for any website 3.1.5 false {46551EC9-40F0-4e47-8E18-8E5CF550CFB8} TinEye Reverse Image Search 1.3.2 false tineye@ideeinc.com Update Scanner 4.2.0 false {c07d1a49-9894-49ff-a594-38960ede8fb9} Xmarks Bookmark Sync 4.5.0.8 false foxmarks@kei.com

For the avoidance of doubt the issue also occurs in a new profile when there are no extensions enabled..

The speed test has been used for comparison purposes only and shows results of about half those shown by other browsers which show consistent speeds.

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I think something else is going on if you clean installed everything. Did you leave out the A/V to see what happens.

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Hi, yes do check with out your A/V as there are issues with these at times. There is security software like Avast/AVG, Kaspersky, BitDefender and ESET that intercept secure connections and send their own certificate.

So usual is no connect with error messages but can see it slowing things down.

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Thanks, but with AV disabled performance is exactly the same as with it enabled.

Enabling AV has no impact on alternative browsers.