Pasting multiple images from clipboard overwrites previous images in web apps (e.g., Gemini) due to hardcoded "image.png" / "bild.png" filename

[JackRabbit]

Steps to reproduce:

1. Copy an image to the clipboard using any screenshot tool (e.g., Flameshot, Gnome-screenshot) on Linux.

2. Open a web application that allows multiple file uploads and checks for duplicate filenames (such as Google Gemini).

3. Paste the image using Ctrl+V. The browser automatically assigns it the generic filename "image.png" (or "bild.png" in the localized Swedish version).

4. Take a new, different screenshot to the clipboard.

5. Paste the new image into the same input field.

Expected behavior: The browser should generate a unique filename for each pasted clipboard image (for example, by appending a timestamp or a counter like image_1.png, image_2.png). This would allow web applications to recognize them as distinct files.

Actual behavior: Firefox assigns the exact same static filename ("image.png" or "bild.png") to every image pasted from the clipboard. As a result, web apps assume the user is trying to upload the same file twice. It either overwrites the first image or rejects the second one completely. This breaks the workflow for power users, making it impossible to paste multiple screenshots into the same chat prompt without manually saving them to disk first.

Environment:

• OS: Linux Mint 22.3 (Ubuntu 24.04 noble base)

• Desktop: Cinnamon 6.6.7

• Browser: Firefox

[Jon]

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