1959094 - The existing wallpaper is removed if an unsupported file is uploaded as a Custom wallpaper

Status: NEW

(Firefox :: New Tab Page, defect)

Description

[Valentin Bandac [:vbandac], Ecosystem QA]

[Affected versions]:

• Firefox Beta 138.0b4 - BuildID: 20250407102644
• Firefox Nightly 139.0a1 - BuildID: 20250407091419

[Affected Platforms]:

• Windows 10 x64
• macOS 15.0.1
• Ubuntu 22.04

[Prerequisites]:

• Have a new profile created and opened.
• Have set the “browser.newtabpage.activity-stream.newtabWallpapers.customWallpaper.enabled” pref set to true.
• Have an existing wallpaper from any category (Abstract, Solid colors, Celestial, photographs) already set.

[Steps to reproduce]:

1. Open the browser from the prerequisites.
2. Open a new Tab and click the Personalize New Tab menu.
3. Click the “Upload an image” option and choose an invalid (non-image) file, then click Open.
4. Observe the behavior.

[Expected result]:

• An error message regarding the file type of the selected wallpaper is NOT displayed on the screen.
• The file is not applied to the browser.
• If a wallpaper was previously set, the same wallpaper will remain applied.

[Actual result]:

• An error message regarding the file type of the selected wallpaper is NOT displayed on the screen.
• The file is not applied to the browser.
• The previously set wallpaper is removed and the default wallpaper is applied.

[Notes]:

• This issue is reproducible with all the wallpapers in all categories that were previously set.
• A recording of the issue can e found here.