Using different user-agents for different web pages

[fabriziobagala]

It would be helpful if there was an entry in the Settings that would allow you to set a different user-agent for the specified pages. All of this should be done without using third-party components or plugins. Thank you.

[Jon]

Thanks for submitting an idea to the Mozilla Connect community! Your idea is now open to votes (aka kudos) and comments.

[Honza]

You can use "Responsive Design Mode"

Look for a button on Firefox DevTools Toolbox, it's located on the right hand side. The tooltip of that button says "Responsive Design Mode (Ctrl + Shift + M)" 

Clicking the button activates the responsive design mode with a toolbar allowing you to change the user agent string. 

You can also activate the mode using Firefox Menu -> Tools -> Browser Tools -> Responsive Design Mode

Does it work for you?

[Agentvirtuel]

Hello

Feedback Responsive Design Mode https://firefox-source-docs.mozilla.org/devtools-user/responsive_design_mode/index.html

For illustration purposes
Mozilla/5.0 (Windows NT 6.0; rv:14.0) Gecko/20100101 Firefox/14.0.1

Firefox Color https://addons.mozilla.org/addon/firefox-color

[fabriziobagala]

@Honza Yes, it works. However, some web pages do not display correctly. It certainly depends on the fact that the pages are not responsive. I think it would have been more useful to have an option that only changes the user-agent, without changing the page size. What do you think? In any case, I sincerely appreciate your help.

@Agentvirtuel Thank you very much for the explanatory explanation. The use of imagery was helpful.

[Honza]

Good point. I filed request for an enhancement here:

Bug 1863554 - Using different user-agents for different web pages

Thank you!