diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSession.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSession.java
index d0288d0c8df1..56188b77a3ab 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSession.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSession.java
@@ -6,7 +6,6 @@
 
 package org.mozilla.gecko;
 
-import java.io.File;
 import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -477,16 +476,6 @@ public class GeckoSession implements Parcelable {
             preload(appContext, /* geckoArgs */ null, multiprocess);
         }
 
-        if (mSettings.getString(GeckoSessionSettings.DATA_DIR) == null) {
-            final File dataDir = new File(appContext.getApplicationInfo().dataDir);
-            try {
-                mSettings.setString(GeckoSessionSettings.DATA_DIR,
-                                    dataDir.getCanonicalPath());
-            } catch (final java.io.IOException e) {
-                Log.e(LOGTAG, "Failed to resolve app data directory");
-            }
-        }
-
         final String chromeUri = mSettings.getString(GeckoSessionSettings.CHROME_URI);
         final int screenId = mSettings.getInt(GeckoSessionSettings.SCREEN_ID);
         final boolean isPrivate = mSettings.getBoolean(GeckoSessionSettings.USE_PRIVATE_MODE);
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSessionSettings.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSessionSettings.java
index 8e401e917c99..e7cfa3de672f 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSessionSettings.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSessionSettings.java
@@ -84,12 +84,6 @@ public final class GeckoSessionSettings implements Parcelable {
     public static final Key<Boolean> USE_REMOTE_DEBUGGER =
         new Key<Boolean>("useRemoteDebugger");
 
-    public static final Key<String> DEBUGGER_SOCKET_DIR =
-        new Key<String>("debuggerSocketDir");
-
-    /* package */ static final Key<String> DATA_DIR =
-        new Key<String>("dataDir", /* initOnly */ true, /* values */ null);
-
     private final GeckoSession mSession;
     private final GeckoBundle mBundle;
 
@@ -108,7 +102,6 @@ public final class GeckoSessionSettings implements Parcelable {
         mBundle.putBoolean(USE_MULTIPROCESS.name, true);
         mBundle.putInt(DISPLAY_MODE.name, DISPLAY_MODE_BROWSER);
         mBundle.putBoolean(USE_REMOTE_DEBUGGER.name, false);
-        mBundle.putString(DEBUGGER_SOCKET_DIR.name, null);
     }
 
     /* package */ GeckoSessionSettings(final GeckoSessionSettings settings,
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java
index 5d8909766ca9..2b7dd781a5b0 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java
@@ -125,6 +125,13 @@ public final class GeckoLoader {
             }
         }
 
+        try {
+            final File dataDir = new File(context.getApplicationInfo().dataDir);
+            putenv("MOZ_ANDROID_DATA_DIR=" + dataDir.getCanonicalPath());
+        } catch (final java.io.IOException e) {
+            Log.e(LOGTAG, "Failed to resolve app data directory");
+        }
+
         putenv("MOZ_ANDROID_PACKAGE_NAME=" + context.getPackageName());
 
         setupDownloadEnvironment(context);
diff --git a/mobile/android/modules/geckoview/GeckoViewRemoteDebugger.jsm b/mobile/android/modules/geckoview/GeckoViewRemoteDebugger.jsm
index 25ead7c4afb4..4fe8948955f2 100644
--- a/mobile/android/modules/geckoview/GeckoViewRemoteDebugger.jsm
+++ b/mobile/android/modules/geckoview/GeckoViewRemoteDebugger.jsm
@@ -50,15 +50,23 @@ class GeckoViewRemoteDebugger extends GeckoViewModule {
         "resource://gre/modules/dbg-browser-actors.js");
       DebuggerServer.allowChromeProcess = true;
     }
-    this._isEnabled = true;
-    this._usbDebugger.stop();
 
     let windowId = this.window.QueryInterface(Ci.nsIInterfaceRequestor)
                               .getInterface(Ci.nsIDOMWindowUtils)
                               .outerWindowID;
-    let portOrPath = (this.settings.debuggerSocketDir || this.settings.dataDir) +
-                     "/firefox-debugger-socket-" +
-                     windowId;
+    let env = Cc["@mozilla.org/process/environment;1"]
+              .getService(Ci.nsIEnvironment);
+    let dataDir = env.get("MOZ_ANDROID_DATA_DIR");
+
+    if (!dataDir) {
+      debug("Missing env MOZ_ANDROID_DATA_DIR - aborting debugger server start");
+      return;
+    }
+
+    this._isEnabled = true;
+    this._usbDebugger.stop();
+
+    let portOrPath = dataDir + "/firefox-debugger-socket-" + windowId;
     this._usbDebugger.start(portOrPath);
   }