diff --git a/extensions/firefox/bootstrap.js b/extensions/firefox/bootstrap.js
index 16d508f88..1c141190a 100644
--- a/extensions/firefox/bootstrap.js
+++ b/extensions/firefox/bootstrap.js
@@ -45,11 +45,13 @@ function log(str) {
 }
 
 function initializeDefaultPreferences() {
+  /* eslint-disable semi */
   var DEFAULT_PREFERENCES =
 //#include ../../web/default_preferences.json
 //#if false
-    "end of DEFAULT_PREFERENCES";
+    "end of DEFAULT_PREFERENCES"
 //#endif
+  /* eslint-enable semi */
 
   var defaultBranch = Services.prefs.getDefaultBranch(EXT_PREFIX + ".");
   var defaultValue;
diff --git a/extensions/firefox/content/PdfJs.jsm b/extensions/firefox/content/PdfJs.jsm
index 1cd4259b8..b02cc6e87 100644
--- a/extensions/firefox/content/PdfJs.jsm
+++ b/extensions/firefox/content/PdfJs.jsm
@@ -79,11 +79,13 @@ function isDefaultHandler() {
 }
 
 function initializeDefaultPreferences() {
+  /* eslint-disable semi */
   var DEFAULT_PREFERENCES =
 //#include ../../../web/default_preferences.json
 //#if false
-    "end of DEFAULT_PREFERENCES";
+    "end of DEFAULT_PREFERENCES"
 //#endif
+  /* eslint-enable semi */
 
   var defaultBranch = Services.prefs.getDefaultBranch(PREF_PREFIX + ".");
   var defaultValue;
diff --git a/extensions/firefox/content/PdfjsChromeUtils.jsm b/extensions/firefox/content/PdfjsChromeUtils.jsm
index af7b4c2fb..0fcc18430 100644
--- a/extensions/firefox/content/PdfjsChromeUtils.jsm
+++ b/extensions/firefox/content/PdfjsChromeUtils.jsm
@@ -33,11 +33,13 @@ XPCOMUtils.defineLazyServiceGetter(Svc, "mime",
                                    "@mozilla.org/mime;1",
                                    "nsIMIMEService");
 
+/* eslint-disable semi */
 var DEFAULT_PREFERENCES =
 //#include ../../../web/default_preferences.json
 //#if false
-  "end of DEFAULT_PREFERENCES";
+  "end of DEFAULT_PREFERENCES"
 //#endif
+/* eslint-enable semi */
 
 var PdfjsChromeUtils = {
   // For security purposes when running remote, we restrict preferences