--- a/.eslintignore
+++ b/.eslintignore
@@ -84,20 +84,18 @@ browser/components/translation/cld2/**
 # their own lint rules currently.
 browser/extensions/followonsearch/**
 browser/extensions/screenshots/**
 browser/extensions/pdfjs/content/build**
 browser/extensions/pdfjs/content/web**
 # generated or library files in pocket
 browser/extensions/pocket/content/panels/js/tmpl.js
 browser/extensions/pocket/content/panels/js/vendor/**
-# generated or library files in activity-stream
-browser/extensions/activity-stream/data/content/activity-stream.bundle.js
-browser/extensions/activity-stream/test/**
-browser/extensions/activity-stream/vendor/**
+# Activity Stream has incompatible eslintrc. `npm run lint` from its directory
+browser/extensions/activity-stream/**
 # The only file in browser/locales/ is pre-processed.
 browser/locales/**
 # imported from chromium
 browser/extensions/mortar/**
 # Generated data files
 browser/extensions/formautofill/phonenumberutils/PhoneNumberMetaData.jsm
 
 # devtools/ exclusions

--- a/.flake8
+++ b/.flake8
@@ -1,11 +1,12 @@
 [flake8]
 # See http://pep8.readthedocs.io/en/latest/intro.html#configuration
 ignore = E121, E123, E126, E129, E133, E226, E241, E242, E704, W503, E402, E741
 max-line-length = 99
 exclude =
     browser/extensions/mortar/ppapi/,
     build/pymake/,
+    node_modules,
     security/nss/,
     testing/mochitest/pywebsocket,
     tools/lint/test/files,
 

--- a/tools/lint/cpp-virtual-final.yml
+++ b/tools/lint/cpp-virtual-final.yml
@@ -1,16 +1,17 @@
 ---
 cpp-virtual-final:
     description: "Virtual function declarations should specify only one of
                   `virtual`, `final`, or `override`"
     level: warning
     include: ['.']
     exclude:
         # Third-party code with cpp-virtual-final warnings:
+        - '**/node_modules'
         - gfx/angle
         - gfx/skia
         - media/webrtc/trunk
         - security/sandbox/chromium
     extensions: ['cpp', 'h', 'mm']
     type: regex
     #
     # This lint warns about: