Where to put user.js?

[NonlinearFruit]

I was hoping to be able to provide Zen with a user.js so that I could version control the preferences.

• Does Zen allow for a user.js?
• What directory does it belong in?

Here is the user.js I was fiddling with to see if it would work:

user_pref("zen.theme.accent-color", "#ffffff");
user_pref("zen.sidebar.data", "");
user_pref("toolkit.telemetry.pioneer-new-studies-available", false);

• ~/.mozilla/firefox/{{profile}}/user.js works for Firefox
• ~/.zen/{{profile}}/user.js didn't work for Zen (default profile root directory)
• ~/.var/app/io.github.zen_browser.zen/cache/zen/{{profile}}/user.js didn't work for Zen work either (default profile local directory)

Using Zen 1.0.0-a.28 (64-bit) from Flathub on Fedora Linux 39