Firebase error

docs/faq.rst

@@ -30,3 +30,14 @@ For example, when you visit https://epigenomegateway.wustl.edu/browser, and you
 a custome track hosted at http://your.track.url.bigwig, the browser will display ``Data fetch failed``
 for that track because due to security settings, the browser in HTTPS page cannot access HTTP resource.
 In such case you can use http://epigenomegateway.wustl.edu/browser instead (without the ``s``).
+
+Firebase fetal error
+--------------------
+
+After you installed a new mirror, when you start your mirror instance by running ``npm start``, if you see
+a Firebase fetal error like following:
+
+.. image:: _static/firebase_error.png
+
+This means you need to setup a Firebase database for the Session/Live function to work properly,
+check :ref:`Firebase_setup` please

docs/installation.rst

@@ -16,6 +16,8 @@ Start the browser
     This step will install dependent packages.
 #. Type ``npm start``
 
+.. warning:: if ``npm install`` gives you error, you might try ``npm install --force``.
+
 That's it! You are done with your mirror site.
 The browser is now accessible from http://localhost:3000/browser.
 
@@ -42,6 +44,8 @@ Then prepare your gene annotation files like the ones for ``hg19``, ``mm10`` etc
 Now your own backend API is running, change ``AWS_API`` variable to empty string in ``GeneSource.js`` file.
 After this you are using your own API for gene annotation tracks and gene search.
 
+.. _Firebase_setup:
+
 Firebase setup
 --------------