diff --git a/mail/app/profile/all-thunderbird.js b/mail/app/profile/all-thunderbird.js
index 78e2846ba0..eda5bfcdee 100644
--- a/mail/app/profile/all-thunderbird.js
+++ b/mail/app/profile/all-thunderbird.js
@@ -405,6 +405,7 @@ pref("browser.display.auto_quality_min_font_size", 0);
 
 pref("view_source.syntax_highlight", false);
 
+pref("dom.serviceWorkers.enabled", true);
 
 /////////////////////////////////////////////////////////////////
 // End core all.js pref overrides