1466320 - Headless Firefox will not start.

Status: RESOLVED WORKSFORME

(Firefox :: Headless, defect)

Description

[midna]

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0
Build ID: 20180601222241

Steps to reproduce:

- Run a new command line window;
- Type: "C:\Program Files\Firefox Nightly\firefox.exe" -headless https://example.com
(The installation path depends of the system).

You may also use the -screenshot flag instead of -headless.
You may also specify the "-P newprofile" option to use a clean profile.

Note that no other session of Firefox must be running.


Actual results:

A Firefox process starts but nothing happens. The Web browser uses between 16 and 19MB of RAM (by specifying the -P option to use a fresh profile). If run under my own profile (by not specifying the -P flag), it uses 65MB of RAM, which means the Firefox addons may load.

The same result happens with the -screenshot flag, yet no screenshot is actually written.

I ran these tests under two different computers, both running Microsoft Windows 7 Professional SP1 (x64) with Mozilla Firefox 62.0a1 (2018-06-01) (x64).


Expected results:

The Web browser should have started and displayed the webpage in Headless mode. Using the -screenshot flag, it should have captured the web page into a PNG file under the command-line's active directory.

Comment 1

[Adrian Florinescu [:aflorinescu]]

Thanks for the report.
I've tested on Windows 7, Windows 10 and Ubuntu 16.04 using the latest nightly and latest release versions:
60.0.2 -20180605171542
62.0a1 -20180613100146
with the following results:

According to https://developer.mozilla.org/en-US/Firefox/Headless_mode, using -headless parameter is supposed to open Firefox without UI, which according to comment 0 and my tests this happens. 
Using -screenshot, Firefox is supposed to screenshot a target site and put the screenshot into the local file "screenshot.png". 
I can see the expected behavior on Ubuntu 16.04, Windows 10 and on Windows 7 (If my understanding is correct, the -screenshot mode should have headless mode, take a screenshot, then close.). The location of the file should be "C:\Users\your_username\" and if Firefox has issues writing there, that would explain the bug. Can you please verify that there are writing permissions allowed on your local location?

Based on the above, I'll mark this issue as works for me and assign it to headless component.
Please reopen this issue if I missed something.