1288551 - browser.reader settings intermittently ignored

Status: UNCONFIRMED

(Testing :: General, defect, P3)

Description

[tallus]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:47.0) Gecko/20100101 Firefox/47.0
Build ID: 20160606114208

Steps to reproduce:

I am running a Selenium test with Firefox 47.0 and the Marionette driver on Ubuntu 14.04 using Selenium with Python.

I set a profile with browser.reader.detectedFirstArticle to true*

The tests consists of:

1. Loading a Page
2. Clicking on a link to load another page
3. Click on another link to load a third page

* I set other options to disable it but it made no difference


Actual results:

The tests intermittently fail (approximately  50% of  the time) on step 3 as the popup introducing the Reader View covers the link after the second page is loaded in step 2

This is despite  browser.reader.detectedFirstArticle being set so it should not appear.
I have confirmed this by examining about:config at the test.

However if I introduce a delay of 0.5 secs or more after step 1 the popup never appears. A delay of 0.1 secs at this stage was not sufficient.

Since automated browser operations happen faster than if a human were doing it is it possible that the code that displays the pop-up is triggered before the profile is loaded? 


Expected results:

The popup should never be displayed if  browser.reader.detectedFirstArticle is true.