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What is the Firefox equivalent of Windows' %username%?

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  • Impendulo yokugqibela ngu cor-el

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I'm trying to setup username variables in about:config, notably default download location and browser.cache.disk.parent_directory . When I use the standard %username% variable in these settings, Firefox interprets them literally. Does Firefox have an equivalent %username% variable?

This happened

Every time Firefox opened

== Always

I'm trying to setup username variables in about:config, notably default download location and browser.cache.disk.parent_directory . When I use the standard %username% variable in these settings, Firefox interprets them literally. Does Firefox have an equivalent %username% variable? == This happened == Every time Firefox opened == Always

All Replies (4)

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No. You do not have access to environment variables on the about:config page.

You can get that value via the Tools > Error Console if necessary. Copy and Paste this code in the Code field and click evaluate.

Components.classes["@mozilla.org/process/environment;1"].getService(Components.interfaces.nsIEnvironment).get('USERNAME');

Ilungisiwe ngu cor-el

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With that code snippet, can the response be injected into the browser.cache.disk.parent_directory setting?

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An extension should be able to do that quite easily.
Try this code in the Tools Error Console.
You can create an extension to make the change.

const Cc = Components.classes, Ci = Components.interfaces;
var PB = Cc["@mozilla.org/preferences-service;1"].getService(Ci.nsIPrefService).getBranch("");
var PN = "browser.cache.disk.parent_directory";
var curVal = PB.getCharPref(PN);
var userName = Cc["@mozilla.org/process/environment;1"].getService(Ci.nsIEnvironment).get('USERNAME');
newVal = curVal.replace(/%USERNAME%/i, userName);
PB.setCharPref(PN, newVal);

See also:

Ilungisiwe ngu cor-el

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By "create an extension", do you mean just paste that code into a XPI?