The most powerful user agent script I've tried

It help me with STUPID SPOTIFY drop support for non-quantum last version of Firefox

Update "Mozilla Firefox" to version 66.
(((Screenshot ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_12maya2019g.1557639594.png
As it is made in another addition
(((Screenshot ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_12maya2019g.1557639603.png
There are websites where newer version of the browser is already required...
"You use the irrelevant version of the browser"
(((Screenshot ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_12maya2019g.1557641931.png
And after your updates of addition the situation in the browser does not change in a root, Firefox 61 is already outdated. It would be time to update till 66-67 the version.
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Обновите "Mozilla Firefox" до версии 66.
(((Скриншот ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_12maya2019g.1557639594.png
Как сделано это в другом дополнение
(((Скриншот ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_12maya2019g.1557639603.png
Есть сайты где уже требуется более новая версия браузера...
"Вы используете неактуальную версию браузера"
(((Скриншот ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_12maya2019g.1557641931.png
И после ваших обновлений дополнения ситуация в браузере не меняется в корне, Firefox 61 является уже устаревшим. Пора бы обновить до 66-67 версии.
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P.S. (((Three days later.
Alexander, thanks for the help in settings, it turned out to dump.
Screenshot ➜ http://ipic.su/img/img7/fs/Ashampoo_Snap_15maya2019g.1557929062.png

No longer actively maintained. Bug reports are responded to with requests for "donations to motivate the author".

Compatible with Waterfox! Very customisable and powerful add-on, allowing selecting a specific agent for each visited domain. It has two different interfaces, one more "user friendly" and another more "programmer friendly". One problem with this add-on is its size (4 MB file / 21 MB installed). Recently (2020/10) tested it against other much smaller UA switchers and didn't notice any advantages. Downvoting for rudeness on description Page, though.

Very good extension, but too sad the recent version have stopped working with Firefox. I hope this bug can be fixed if possible. :)

The newest version can be installed on a old version of Firefox (using version 56 myself) by going to this url: https://bugzilla.mozilla.org/show_bug.cgi?id=1549017

Follow the instruction written on the 3rd and 5th comment. 3rd:

"Full Procedure:

Go to about:support in the URL bar.
Open your profile directory.".....

5th comment:

I prefer the temporary fix that I outlined here:

https://www.reddit.com/r/firefox/comments/bkcjoa/all_of_my_addons_got_disabled_and_they_are_all/emggvbx/

A temporary workaround:...

Thanks the ones with the ideas, not me. :)

👍👍👍👍👍👍

Ótimo complemento. Por favor faça uma versão para Google Chrome também. Obrigado pelo ótimo complemento.

Add-on is super! Perfectly hides information, except whatleaks ...;) I wish good luck!

So easy to use, unless you have a serious brain disability but in this case you should be in a specialized hospital (yep a read some 1 star reviews = UNBELIEVABLE about why they put 1 star!!!)

A top of the line add-on, strongly recommended!

Yes sure we would like more options in the user agent or more operating system and browsers choices, but it's just to be able to put more mess with websites who spy on us... I got an idea why not an input where we can input a "home made" user-agent ROTFL hahaha ;)

In all case this add-on spoof very well Instagram to upload pictures from your desktop computer, just select any smartphone, reload the page and you are set with the + tab/button at the bottom!!

Thanks a lot Alexander Schlarb, it's very good add-on

Kenapa pas buka layarnya hitam ga ada tulisanya😬

Doesn't include instructions on how to use it.

It's easy to use, very intuitive, and lightweight. That's all I care about, it's a damn UA switcher.