diff --git a/mobile/android/base/java/org/mozilla/gecko/GeckoApplication.java b/mobile/android/base/java/org/mozilla/gecko/GeckoApplication.java
index dbd57d72ebc8..f18c879ae994 100644
--- a/mobile/android/base/java/org/mozilla/gecko/GeckoApplication.java
+++ b/mobile/android/base/java/org/mozilla/gecko/GeckoApplication.java
@@ -937,6 +937,7 @@ public class GeckoApplication extends Application
         if (GeckoPreferences.PREFS_SYSTEM_FONT_SIZE.equals(key)) {
             final boolean enabled = prefs.getBoolean(GeckoPreferences.PREFS_SYSTEM_FONT_SIZE, false);
             getRuntime().getSettings().setAutomaticFontSizeAdjustment(enabled);
+            getRuntime().getSettings().setFontInflationEnabled(enabled);
         }
     }
 }
diff --git a/mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/RuntimeSettingsTest.kt b/mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/RuntimeSettingsTest.kt
index 511cc7ae7d33..f27fb73368b9 100644
--- a/mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/RuntimeSettingsTest.kt
+++ b/mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/RuntimeSettingsTest.kt
@@ -41,7 +41,7 @@ class RuntimeSettingsTest : BaseSessionTest() {
         assertThat("Gecko font scale should match system font scale",
                 settings.fontSizeFactor.toDouble(), closeTo(expectedFontSizeFactor.toDouble(), 0.05))
         assertThat("font inflation enabled",
-                settings.fontInflationEnabled, `is`(true))
+                settings.fontInflationEnabled, `is`(initialFontInflation))
 
         settings.automaticFontSizeAdjustment = false
         assertThat("Gecko font scale restored to previous value",
@@ -65,7 +65,7 @@ class RuntimeSettingsTest : BaseSessionTest() {
         assertThat("Gecko font scale should match system font scale",
                 settings.fontSizeFactor.toDouble(), closeTo(expectedFontSizeFactor.toDouble(), 0.05))
         assertThat("font inflation enabled",
-                settings.fontInflationEnabled, `is`(true))
+                settings.fontInflationEnabled, `is`(initialFontInflation))
 
         settings.automaticFontSizeAdjustment = false
         assertThat("Gecko font scale restored to previous value",
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoFontScaleListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoFontScaleListener.java
index e1edc289313b..4c26bf7dd6f1 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoFontScaleListener.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoFontScaleListener.java
@@ -18,7 +18,7 @@ import android.support.annotation.UiThread;
 import android.util.Log;
 
 /**
- * A class that automatically adjusts font size and font inflation settings for web content in Gecko
+ * A class that automatically adjusts font size settings for web content in Gecko
  * in accordance with the device's OS font scale setting.
  *
  * @see android.provider.Settings.System#FONT_SCALE
@@ -41,7 +41,6 @@ import android.util.Log;
     private boolean mRunning;
 
     private float mPrevGeckoFontScale;
-    private boolean mPrevFontInflationState;
 
     public static GeckoFontScaleListener getInstance() {
         return sInstance;
@@ -131,7 +130,6 @@ import android.util.Log;
         }
 
         mPrevGeckoFontScale = mSettings.getFontSizeFactor();
-        mPrevFontInflationState = mSettings.getFontInflationEnabled();
         ContentResolver contentResolver = mApplicationContext.getContentResolver();
         Uri fontSizeSetting = Settings.System.getUriFor(Settings.System.FONT_SCALE);
         contentResolver.registerContentObserver(fontSizeSetting, false, this);
@@ -155,17 +153,13 @@ import android.util.Log;
     private void onSystemFontScaleChange(final ContentResolver contentResolver,
                                          final boolean stopping) {
         float fontScale;
-        boolean fontInflationEnabled;
 
         if (!stopping) { // Either we were enabled, or else the system font scale changed.
             fontScale = Settings.System.getFloat(contentResolver, Settings.System.FONT_SCALE, DEFAULT_FONT_SCALE);
-            fontInflationEnabled = true;
         } else { // We were turned off.
             fontScale = mPrevGeckoFontScale;
-            fontInflationEnabled = mPrevFontInflationState;
         }
 
-        mSettings.setFontInflationEnabledInternal(fontInflationEnabled);
         mSettings.setFontSizeFactorInternal(fontScale);
     }
 
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoRuntimeSettings.java b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoRuntimeSettings.java
index f82683c98b1e..ae01da2601ad 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoRuntimeSettings.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoRuntimeSettings.java
@@ -743,10 +743,10 @@ public final class GeckoRuntimeSettings extends RuntimeSettings {
 
     /**
      * Set whether or not font sizes in web content should be automatically scaled according to
-     * the device's current system font scale setting.
-     * Disabling this setting will restore the previously used values for
-     * {@link GeckoRuntimeSettings#getFontSizeFactor()} and
-     * {@link GeckoRuntimeSettings#getFontInflationEnabled()}.
+     * the device's current system font scale setting. Enabling this will prevent modification of
+     * {@link GeckoRuntimeSettings#setFontSizeFactor()}.
+     * Disabling this setting will restore the previously used value for
+     * {@link GeckoRuntimeSettings#getFontSizeFactor()}.
      *
      * @param enabled A flag determining whether or not font sizes should be scaled automatically
      *                to match the device's system font scale.
@@ -835,7 +835,7 @@ public final class GeckoRuntimeSettings extends RuntimeSettings {
         }
 
         final int fontSizePercentage = Math.round(fontSizeFactor * 100);
-        mFontSizeFactor.commit(Math.round(fontSizePercentage));
+        mFontSizeFactor.commit(fontSizePercentage);
         if (getFontInflationEnabled()) {
             final int scaledFontInflation = Math.round(FONT_INFLATION_BASE_VALUE * fontSizeFactor);
             mFontInflationMinTwips.commit(scaledFontInflation);
@@ -866,21 +866,10 @@ public final class GeckoRuntimeSettings extends RuntimeSettings {
      *
      * <p>Currently, any changes only take effect after a reload of the session.
      *
-     * <p>This setting cannot be modified while
-     * {@link GeckoRuntimeSettings#setAutomaticFontSizeAdjustment automatic font size adjustment}
-     * is enabled.
-     *
      * @param enabled A flag determining whether or not font inflation should be enabled.
      * @return This GeckoRuntimeSettings instance.
      */
     public @NonNull GeckoRuntimeSettings setFontInflationEnabled(final boolean enabled) {
-        if (getAutomaticFontSizeAdjustment()) {
-            throw new IllegalStateException("Not allowed when automatic font size adjustment is enabled");
-        }
-        return setFontInflationEnabledInternal(enabled);
-    }
-
-    /* package */ @NonNull GeckoRuntimeSettings setFontInflationEnabledInternal(final boolean enabled) {
         final int minTwips =
                 enabled ? Math.round(FONT_INFLATION_BASE_VALUE * getFontSizeFactor()) : 0;
         mFontInflationMinTwips.commit(minTwips);
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/doc-files/CHANGELOG.md b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/doc-files/CHANGELOG.md
index ea94f25dd08e..ccda0946e974 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/doc-files/CHANGELOG.md
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/doc-files/CHANGELOG.md
@@ -8,6 +8,13 @@ exclude: true
 
 <h1> GeckoView API Changelog. </h1>
 
+## v69
+- Modified behavior of ['setAutomaticFontSizeAdjustment'][69.1] so that it no 
+  longer has any effect on ['setFontInflationEnabled'][69.2]
+
+[69.1]: ./GeckoRuntimeSettings.html#setAutomaticFontSizeAdjustment-boolean-
+[69.2]: ./GeckoRuntimeSettings.html#setFontInflationEnabled-boolean-
+
 ## v68
 - Added [`GeckoRuntime#configurationChanged`][68.1] to notify the device
   configuration has changed.