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Add-Ons page recognizing wrong Firefox version

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  • 1 has this problem
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  • Last reply by linoleum

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I have installed Firefox 65.0 on Debian Stretch following the instructions on this website: https://linuxconfig.org/how-to-install-latest-firefox-browser-on-debian-9-stretch-linux. When I execute "firefox --version" on my terminal I get "Mozilla Firefox 65.0", the same which is shown in "Help -> About Firefox".

However, when I try to install some add-ons I get a warning "You're using Firefox 51.0"- it seems to think that I'm still using the old version. Am I? How can I fix it?

I have installed Firefox 65.0 on Debian Stretch following the instructions on this website: https://linuxconfig.org/how-to-install-latest-firefox-browser-on-debian-9-stretch-linux. When I execute "firefox --version" on my terminal I get "Mozilla Firefox 65.0", the same which is shown in "Help -> About Firefox". However, when I try to install some add-ons I get a warning "You're using Firefox 51.0"- it seems to think that I'm still using the old version. Am I? How can I fix it?
Attached screenshots

Chosen solution

The User Agent you used to post this thread is Mozilla/5.0 (Windows NT 10.0; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0

So it appears to be either from a UA related Extension you have installed or it was manually modified.

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

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Chosen Solution

The User Agent you used to post this thread is Mozilla/5.0 (Windows NT 10.0; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0

So it appears to be either from a UA related Extension you have installed or it was manually modified.

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

Modified by James

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You're right. It was manually modified by an old add-on I had already removed a long time ago. The link you provided solved the issue, thanks.