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how do I set the screen sizes for responsive design view?

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  • Last reply by cor-el

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I previously was able to select one of several standard screen sizes for responsive design view when testing a website but now can only select one size. Why and how do I change this?

I previously was able to select one of several standard screen sizes for responsive design view when testing a website but now can only select one size. Why and how do I change this?

Chosen solution

Is the drop down list on the responsive design view window empty?

Do you have a devtools.responsiveUI.presets pref on the about:config page?

If that is the case then try to reset this pref to get the default built-in presets.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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Chosen Solution

Is the drop down list on the responsive design view window empty?

Do you have a devtools.responsiveUI.presets pref on the about:config page?

If that is the case then try to reset this pref to get the default built-in presets.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.