--- a/toolkit/components/telemetry/TelemetryEnvironment.jsm
+++ b/toolkit/components/telemetry/TelemetryEnvironment.jsm
@@ -222,16 +222,17 @@ const DEFAULT_ENVIRONMENT_PREFS = new Ma
   ["extensions.formautofill.addresses.enabled", {what: RECORD_PREF_VALUE}],
   ["extensions.formautofill.creditCards.enabled", {what: RECORD_PREF_VALUE}],
   ["extensions.legacy.enabled", {what: RECORD_PREF_VALUE}],
   ["extensions.strictCompatibility", {what: RECORD_PREF_VALUE}],
   ["extensions.update.enabled", {what: RECORD_PREF_VALUE}],
   ["extensions.update.url", {what: RECORD_PREF_VALUE}],
   ["extensions.update.background.url", {what: RECORD_PREF_VALUE}],
   ["extensions.screenshots.disabled", {what: RECORD_PREF_VALUE}],
+  ["general.config.filename", {what: RECORD_DEFAULTPREF_VALUE}],
   ["general.smoothScroll", {what: RECORD_PREF_VALUE}],
   ["gfx.direct2d.disabled", {what: RECORD_PREF_VALUE}],
   ["gfx.direct2d.force-enabled", {what: RECORD_PREF_VALUE}],
   ["layers.acceleration.disabled", {what: RECORD_PREF_VALUE}],
   ["layers.acceleration.force-enabled", {what: RECORD_PREF_VALUE}],
   ["layers.async-pan-zoom.enabled", {what: RECORD_PREF_VALUE}],
   ["layers.async-video-oop.enabled", {what: RECORD_PREF_VALUE}],
   ["layers.async-video.enabled", {what: RECORD_PREF_VALUE}],