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Change Developer Tools Responsive Design Mode default resolution

jab_creations
jab_creations
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I'm a web developer and I've been using the web developer Responsive Design Mode for some testing.

Unfortunately the default resolution is 320x480 and while I do occasionally test this resolution (it's our bare minimal mobile resolution) it's obnoxious to have to always choose the drop down menu to change the resolution every-single-time!

I've already searched through about:config settings for queries such as 320 and 480 separately.

So: how do I change the Responsive Design Mode default resolution?

I'm a web developer and I've been using the web developer Responsive Design Mode for some testing. Unfortunately the default resolution is 320x480 and while I do occasionally test this resolution (it's our bare minimal mobile resolution) it's obnoxious to have to always choose the drop down menu to change the resolution every-single-time! I've already searched through about:config settings for queries such as 320 and 480 separately. So: how do I change the Responsive Design Mode default resolution?
Attached screenshots

All Replies (3)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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Your browser identified itself as Waterfox on a basis of an older version of Firefox, so this may or may not apply to you.

My Firefox always re-uses the last resolution. In about:config, I notice these preferences, which could be the way that happens:

  • devtools.responsive.userAgent
  • devtools.responsive.viewport.height
  • devtools.responsive.viewport.pixelRatio
  • devtools.responsive.viewport.width

Or maybe it's something in

[profile.folder]\storage\permanent\indexeddb+++fx-devtools\idb

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Didn't you found these two prefs ?

  • devtools.responsive.viewport.height = 480
  • devtools.responsive.viewport.width = 320
jab_creations
jab_creations Question owner
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@jscher2000 That works in Firefox however since they destroyed Firefox as of 57.0 I rarely test it.

I did a fairly thorough search of the Waterfox Classic files and I just can't find anything correlating to a preference let alone the DOM used for the Responsive Design Mode tool.