Therefore, Mozilla removed the site specific user-agent override setting from Firefox 71. One workaround for this, as mentioned in a previous article, is to use a global user-agent. The main problem with the solution is that the set user-agent is used on every site you visit in the Firefox web browser.
And while I warned you that it might have some side effects, initially I didn’t care about any other than returning YouTube to its old design. A few days later, when I visited a banking website, I found that a message was being displayed on it which read something like “Upgrade your browser to access the website”. Sometimes, one or two websites won’t load at all. I ignored them because I thought it was a server issue, but my friends told me they could access the sites from their browsers (Firefox too).
That’s when it hit me, surely the user-agent setting is messing with other websites. Of course, disabling the setting ensured that these websites would work as they normally do. Ironic, isn’t it? You set the option to access certain websites, but it breaks others. I was looking for a solution and literally the only option is to use the User-Agent Switcher extension.
After some research and testing (and looking for alternatives to existing add-ons), I found an add-on that lets me use user-agents on a per-site basis. The extension is called Custom UserAgent String. It is written by its author User-Agent Switcher Revived Add-on (not to be confused with the add-on created by Alexander Schlarb). It’s surprising how many add-ons have the same name.
Functionally, both of Liner’s add-ons are quite similar, but the User-Agent Switcher extension only allows you to set a global user agent, which is what we wanted to fix here. However, the custom useragent string lets you set a useragent on a per-site basis. Perfect and very simple to use.
How to use custom useragent string
Install the extension, click its icon and then click the Options button. This will take you to the Settings screen.
Ignore Section I and go to Section II, titled “Predefined UserAgent Strings”. It has two drop-down menus, one to select the browser and operating system, and the other to select the browser’s user-agent.
step 1
Click the box listed under “Enter the desired URL.” You’ll notice that it contains an asterisk *. Delete it and type the address of the website for which you want to set the user-agent in the box. Here’s the weird part: typing a partial address like ghacks.net or www.ghacks.net into the URL box doesn’t link the site correctly, that is, it falls back to Asterisk (which makes it use the user-agent globally).
To avoid this you should use the full address. For example https://www.ghacks.net/ will work.
step 2
Use the box below the setting that reads “Enter a custom UserAgent string or select one from the list above”. This is where you can enter custom user agents for specific websites. You can get the User Agent from the drop-down menu mentioned above. Or, you can use your custom one (for older browser versions that’s probably missing). Click the + button on the right to finish adding the site-specific user-agent; It should appear in the table at the end of the page.
Comment:The custom string option is good for long-term use, even if the add-on is not updated, you can still get the latest user agent from somewhere else and use it.
Let’s look at another example:
Let’s say you want to access Skype on the web. URL should be written like this https://web.skype.com/
user-agent must be Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36
There are 2 other things a custom UserAgent string table is useful for. The checkbox next to each site listed toggles whether to use the user-agent for the entire website (top-level domain) or only for the given address. Clicking the blank gray button at the right end of the table acts as a switch to enable/disable the user-agent.
You can completely disable the Custom UserAgent String add-on by clicking the icon and pressing the Power button.
This method works perfectly fine in Firefox 71. What extension are you using to set a site-specific user-agent?
