[🚀 Feature]: [Ruby] Ability to read all Firefox config preferences as json

[MatzFan]

Feature and motivation

I can set user preferences via the Profile object, but unless I am misreading the docs the API does not seem to provide a way to read the Firefox preferences from an initialized driver. These are stored in prefs.json together with a user.json, if it exists, and are available on the about:config page if you click on the 'Show All' button.

It seems strange to have the ability to set prefs, as below, without the ability to get their values - especially in a use-case where code may dynamically alter prefs and you need to know how one is set at any point in time.

profile = Selenium::WebDriver::Firefox::Profile.new
profile['browser.download.dir'] = "/tmp/webdriver-downloads"
options = Selenium::WebDriver::Firefox::Options.new(profile: profile)
driver = Selenium::WebDriver.for :firefox, options: options

profile['browser.download.dir'] # => undefined method `[]' for #<Selenium::WebDriver::Firefox::Profile:0x00007f5838737c50

Usage example

For example, in Ruby you would get a preference just like setting it:

profile['browser.download.dir']

And/or have a method which returns all the preferences, something like:

profile.prefs # => hash of all prefs and their values

These could either be read from the two json files on disk or by parsing the html table on the about:config page. The latter option would need to be done in a new (background) session as it would require navigating to that page.

[github-actions]

@MatzFan, thank you for creating this issue. We will troubleshoot it as soon as we can.

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Thank you!

[MatzFan]

I forgot to add a link to an old SO question asking for exactly this functionality (for Python):

https://stackoverflow.com/questions/54065022/how-to-read-preferences-get-value-of-profile-setting-from-selenium-firefox-webd

[titusfortner]

We can't do this directly. Needs to be done by Mozilla

[github-actions]

Hi, @MatzFan.
This issue has been determined to require fixes in GeckoDriver.

You can see if the feature is passing in the Web Platform Tests.

If it is something new, please create an Issue with the GeckoDriver team.

Feel free to comment the issues that you raise back in this issue. Thank you.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.