When a user copies an image to the clipboard and pastes it (Ctrl+V) into a web application, Firefox assigns a generic, hardcoded filename to the blob (usually "image.png" in English or "obraz.png" in localized versions). If the user tries to paste a second, different image from the clipboard into the same input field, Firefox assigns the exact same filename to the new image. Many modern AI platforms and web apps (like Gemini, ChatGPT, etc.) check for duplicate filenames to prevent accidental double-uploads. Because Firefox uses the same static name for every pasted clipboard image, the web app rejects the second image with an error like: "A file named image.png has already been attached."
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