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Firefox 91.13.0esr and websites recognizing it as obsoloete Firefox 52

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After some trouble installing and updating that I described in my former questions, I currently run FF 91.13.0esr on my system.

Some websites however claim that I use an obsolete version of FF and refuse to work or work only partially. First I thought that they define the esr itself as obsolete vs. the normal FF version. However when I checked how websites see my FF version I received FF 52 myself:

whatsmybrowser.org/b/SSI2N

When I click on Help / About Firefox I get FF 91.13.0.esr and a green check that it´s uptodate.

So - is there some leftover old data in FF from updating that makes it pretend to be FF 52? In the shared data below the "user agent" seems to do that but I did not use an add-on to change that after I had moved the system from Windows XP SP3 32bit to Windows 10 64 bit.

After some trouble installing and updating that I described in my former questions, I currently run FF 91.13.0esr on my system. Some websites however claim that I use an obsolete version of FF and refuse to work or work only partially. First I thought that they define the esr itself as obsolete vs. the normal FF version. However when I checked how websites see my FF version I received FF 52 myself: whatsmybrowser.org/b/SSI2N When I click on Help / About Firefox I get FF 91.13.0.esr and a green check that it´s uptodate. So - is there some leftover old data in FF from updating that makes it pretend to be FF 52? In the shared data below the "user agent" seems to do that but I did not use an add-on to change that after I had moved the system from Windows XP SP3 32bit to Windows 10 64 bit.

All Replies (7)

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In your Question Details > More system details your User Agent appears to be Mozilla/5.0 (Windows NT 10.0; rv:52.0) Gecko/20100101 Firefox/52.0

https://support.mozilla.org/en-US/kb/how-reset-default-user-agent-firefox

Are you using any useragent related extensions or toggled privacy.resistFingerprinting in about:config ?

https://support.mozilla.org/en-US/kb/firefox-protection-against-fingerprinting

a note, the Fx 91.13.0esr will be the last main update for the old 91.0 ESR channel.

Modified by James

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James said

In your Question Details > More system details your User Agent appears to be Mozilla/5.0 (Windows NT 10.0; rv:52.0) Gecko/20100101 Firefox/52.0 https://support.mozilla.org/en-US/kb/how-reset-default-user-agent-firefox Are you using any useragent related extensions or toggled privacy.resistFingerprinting in about:config ? https://support.mozilla.org/en-US/kb/firefox-protection-against-fingerprinting a note, the Fx 91.13.0esr will be the last main update for the old 91.0 ESR channel.

I had been using an extension to modify the user agent while I still was using FF 52.9 (the last ESR for Windows XP 32 bit). However after migrating to a system with Window 10 64 bit and updating I did not install that addon again. Could the useragent be frozen on the version before the update somehow?

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I get the same results when using your url http://whatsmybrowser.org/b/SSI2N, but when going to http://whatsmybrowser.org the site shows the correct version. see screenshots How did you get to that address?

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I went to http://whatsmybrowser.org/ both times. That site then stated:

"You’re using Firefox 52. Share this with your support team! Just send them the link below: whatsmybrowser.org/b/SSI2N"

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privacy.resistFingerprinting had been and is set to false in my config

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Does the Troubleshooting Information page -- Firefox's own internal report on itself -- show a Firefox 52 user agent? This article has the steps to launch that page: Use the Troubleshooting Information page to help fix Firefox issues.

If that is 52 and not 91:

I can't tell for sure from previous replies: did you check for and remove the preferences mentioned in the support article James linked earlier: How to reset the default user agent on Firefox?

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jscher2000 - Support Volunteer said

Does the Troubleshooting Information page -- Firefox's own internal report on itself -- show a Firefox 52 user agent? This article has the steps to launch that page: Use the Troubleshooting Information page to help fix Firefox issues.

If that is 52 and not 91:

I can't tell for sure from previous replies: did you check for and remove the preferences mentioned in the support article James linked earlier: How to reset the default user agent on Firefox?

Both the version under "More Troubleshooting information" and the version under "About Firefox" are FF 91.13.0esr (64bit) so it is the latest ESR version, only reporting to be a version before updating because of the user agent.

Modified by ConjurerDragon