diff --git a/doc/setup/install.rst b/doc/setup/install.rst
index 7469b7d0ee0..218b7bb5a7d 100644
--- a/doc/setup/install.rst
+++ b/doc/setup/install.rst
@@ -395,6 +395,13 @@ Source installation requires manually installing dependencies:
 
         C:\> npm install -g rtlcss
 
+    It is then necessary to edit the System Environment's variable
+    :envvar:`PATH` and add the folder where `rtlcss.cmd` is located. Typically:
+
+    .. code-block:: console
+
+        C:\Users\<user>\AppData\Roaming\npm\
+
 
 Fetch the sources
 -----------------
diff --git a/odoo/addons/base/models/assetsbundle.py b/odoo/addons/base/models/assetsbundle.py
index abdb09b0d13..b675cb294c0 100644
--- a/odoo/addons/base/models/assetsbundle.py
+++ b/odoo/addons/base/models/assetsbundle.py
@@ -525,6 +525,8 @@ class AssetsBundle(object):
 
     def run_rtlcss(self, source):
         rtlcss = 'rtlcss'
+        if os.name == 'nt':
+            rtlcss = misc.find_in_path('rtlcss.cmd')
         cmd = [rtlcss, '-']