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How can I change the font size of Firefox's inspect text?

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I already try these:

@namespace url(w3.org/1999/xhtml); .CodeMirror, body.theme-body.devtools-monospace { font-family: "Ubuntu Mono", monospace !important; font-size: 30pt !important; }

@namespace url(http://www.w3.org/1999/xhtml); .CodeMirror {

   font-family:    "Ubuntu Mono", monospace !important;
   font-size:      20pt !important;

}

@namespace url(http://www.w3.org/1999/xhtml); @-moz-document url("chrome://browser/content/devtools/.*"){

  • { font-size: 20px !important }

}

I already try these: @namespace url(w3.org/1999/xhtml); .CodeMirror, body.theme-body.devtools-monospace { font-family: "Ubuntu Mono", monospace !important; font-size: 30pt !important; } @namespace url(http://www.w3.org/1999/xhtml); .CodeMirror { font-family: "Ubuntu Mono", monospace !important; font-size: 20pt !important; } @namespace url(http://www.w3.org/1999/xhtml); @-moz-document url("chrome://browser/content/devtools/.*"){ * { font-size: 20px !important } }

All Replies (9)

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What exactly do you want to change (screenshot)?


I usually place code sections in separate file and use a @import rule in userChrome.css and userContent.css.

In this case you need userChrome.css to style various parts of the Inspector. You can see whether code like this that I use works for you (there might be namespace issues).

/* inspector: tree */
@-moz-document url(chrome://devtools/content/markupview/markup-view.xhtml){
 *|* {font-size:10pt!important; font-weight:bold}
 *|*div.tag-line[selected] * {}
}

/* inspector: rules */
@-moz-document url(chrome://devtools/content/styleinspector/cssruleview.xhtml){
 *|* {font-size:10pt!important; font-weight:bold}
}

/* inspector: computed */
@-moz-document url(chrome://devtools/content/styleinspector/computedview.xhtml){
 *|* {font-size:10pt!important; font-weight:bold}
}
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cor-el said

What exactly do you want to change (screenshot)?

I usually place code sections in separate file and use a @import rule in userChrome.css and userContent.css.

In this case you need userChrome.css to style various parts of the Inspector. You can see whether code like this that I use works for you (there might be namespace issues).

/* inspector: tree */
@-moz-document url(chrome://devtools/content/markupview/markup-view.xhtml){
 *|* {font-size:10pt!important; font-weight:bold}
 *|*div.tag-line[selected] * {}
}

/* inspector: rules */
@-moz-document url(chrome://devtools/content/styleinspector/cssruleview.xhtml){
 *|* {font-size:10pt!important; font-weight:bold}
}

/* inspector: computed */
@-moz-document url(chrome://devtools/content/styleinspector/computedview.xhtml){
 *|* {font-size:10pt!important; font-weight:bold}
}

Thanks for your reply, But it's not work. The picture is where I want to change. The font size is too small.

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Thar part should work with this URL:

  • chrome://devtools/content/markupview/markup-view.xhtml

I posted by own code, so you will have to increment the font size I posted above.

Did you use a separate file via @import since this may not work within userChrome.css ?

userChrome.css :

@import url("devtools.css"); /* needs to before @namespace */

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

/* more CSS rules */

devtools.css:

/* inspector: tree */
@-moz-document url(chrome://devtools/content/markupview/markup-view.xhtml){
 *|* {font-size: 30pt !important; font-weight:bold}
 *|*div.tag-line[selected] * {}
}
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cor-el said

Thar part should work with this URL:
  • chrome://devtools/content/markupview/markup-view.xhtml
I posted by own code, so you will have to increment the font size I posted above. Did you use a separate file via @import since this may not work within userChrome.css ? userChrome.css :
@import url("devtools.css"); /* needs to before @namespace */

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

/* more CSS rules */

devtools.css:

/* inspector: tree */
@-moz-document url(chrome://devtools/content/markupview/markup-view.xhtml){
 *|* {font-size: 30pt !important; font-weight:bold}
 *|*div.tag-line[selected] * {}
}

The pic1 is your mean?

I only use pic2 to change browser UI.

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What I wrote above is to create a devtools.css file in the same chrome folder where userChrome.css is located and paste the code in that file instead of pasting the code in the userChrome.css file like you did.

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cor-el said

What I wrote above is to create a devtools.css file in the same chrome folder where userChrome.css is located and paste the code in that file instead of pasting the code in the userChrome.css file like you did.

I found userChrome.css : C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles\7c63xkoc.default\chrome

And as you said, but still the same. Please look pictures. Thank you.

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I rechecked all the code with the DOM Inspector and it looks that some things have been changed.

Hopefully this will work.

devtools.css:

/* Inspector: Tree */
@-moz-document url(chrome://devtools/content/inspector/markup/markup.xhtml){
 body {font-size: 20pt !important; font-weight: bold}
 div.tag-line[selected] * {}
}

/* Inspector: panels */
@-moz-document url(chrome://devtools/content/inspector/inspector.xhtml){

/* Inspector: tab panel */
.tab-panel-box .inspector-tabpanel {font-size:20pt!important; font-weight:bold}

}
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cor-el said

I rechecked all the code with the DOM Inspector and it looks that some things have been changed. Hopefully this will work. devtools.css:
/* Inspector: Tree */
@-moz-document url(chrome://devtools/content/inspector/markup/markup.xhtml){
 body {font-size: 20pt !important; font-weight: bold}
 div.tag-line[selected] * {}
}

/* Inspector: panels */
@-moz-document url(chrome://devtools/content/inspector/inspector.xhtml){

/* Inspector: tab panel */
.tab-panel-box .inspector-tabpanel {font-size:20pt!important; font-weight:bold}

}

It's not working. :'( I use firefox 53.0.3`,have relevance?

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I realize this is not directly on point, but as a possible workaround, if the Inspector is active, the keyboard shortcuts for zoom (Ctrl+) will enlarge the fonts in the developer tools panes.