--- a/browser/extensions/e10srollout/bootstrap.js
+++ b/browser/extensions/e10srollout/bootstrap.js
@@ -79,17 +79,18 @@ function defineCohort() {
                     );
   } else {
     Preferences.reset(PREF_E10S_ADDON_POLICY);
   }
 
   let userOptedOut = optedOut();
   let userOptedIn = optedIn();
   let disqualified = (Services.appinfo.multiprocessBlockPolicy != 0);
-  let testGroup = (getUserSample() < TEST_THRESHOLD[updateChannel]);
+  let testThreshold = TEST_THRESHOLD[updateChannel];
+  let testGroup = (getUserSample() < testThreshold);
   let hasNonExemptAddon = Preferences.get(PREF_E10S_HAS_NONEXEMPT_ADDON, false);
   let temporaryDisqualification = getTemporaryDisqualification();
   let temporaryQualification = getTemporaryQualification();
 
   let cohortPrefix = "";
   if (disqualified) {
     cohortPrefix = "disqualified-";
   } else if (hasNonExemptAddon) {
@@ -106,17 +107,21 @@ function defineCohort() {
     // still be denied by the backend, which is useful so that the E10S_STATUS
     // telemetry probe can be correctly set.
 
     // For these volatile disqualification reasons, however, we must not try
     // to activate e10s because the backend doesn't know about it. E10S_STATUS
     // here will be accumulated as "2 - Disabled", which is fine too.
     setCohort(`temp-disqualified-${temporaryDisqualification}`);
     Preferences.reset(PREF_TOGGLE_E10S);
-  } else if (!disqualified && temporaryQualification != "") {
+  } else if (!disqualified && testThreshold < 1.0 &&
+             temporaryQualification != "") {
+    // Users who are qualified for e10s and on channels where some population
+    // would not receive e10s can be pushed into e10s anyway via a temporary
+    // qualification which overrides the user sample value when non-empty.
     setCohort(`temp-qualified-${temporaryQualification}`);
     Preferences.set(PREF_TOGGLE_E10S, true);
   } else if (testGroup) {
     setCohort(`${cohortPrefix}test`);
     Preferences.set(PREF_TOGGLE_E10S, true);
   } else {
     setCohort(`${cohortPrefix}control`);
     Preferences.reset(PREF_TOGGLE_E10S);