2051114 - The new native Profile Manager UI dropdown menu appears completely blank and empty in the main profile, while working correctly in newly created profiles

Status: UNCONFIRMED

(Toolkit :: Startup and Profile System, defect)

Description

[sergey]

Attachment: bug-profile-manager-ui-is-completely-blank-empty-in-my-main-v0-pl9dmuhxxv7h1.webp

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0

Steps to reproduce:

Open Firefox using a long-standing, active main profile.
Click on the new native Profile Manager UI dropdown menu to switch profiles or manage them.

Troubleshooting steps taken (did not work):
Restored toolbar defaults via Customize Toolbar.
Toggled the browser.profiles.enabled preference in about:config.
Cleared Startup Cache via about:support.
Deleted xulstore.json inside the profile folder to reset the UI layout.
Attempted manual data migration to a fresh profile.

What resolved the issue:

Completely deleting the Profile Groups folder from the root Firefox data directory (e.g., %appdata%\Mozilla\Firefox on Windows). Upon restarting the browser, Firefox automatically regenerated this folder, and the profile dropdown menu began functioning perfectly again.

Possible cause:

The issue appears to be caused by corruption or data desynchronization within the internal SQLite database stored inside the Profile Groups directory. The new native Profile Manager UI relies on this database to map and render the profile list and management items. If this database falls into an invalid state, ProfilesDatastoreService seemingly fails to self-heal or handle the exception properly, resulting in a silent UI failure that renders a completely blank dropdown.

Actual results:

The profiles dropdown menu appears completely blank and empty. No profiles are listed, and options like "+ New profile" or "Copy this profile" are missing entirely.

Expected results:

The dropdown menu should display the list of available profiles along with native management options ("+ New profile", "Copy this profile", etc.), exactly as it does when creating a fresh, clean profile.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Toolkit::Startup and Profile System' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.