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Why is Firefox downloading .htm files on my computer?

  • 3 replies
  • 1 has this problem
  • 3 views
  • Last reply by cor-el

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Without explanation or my consent, Firefox will occasionally download a .htm file into Downloads in the browser. Today it was WjZ510Su.htm

This has been happening randomly for a few months. What are these files? Without knowing what they are, I always delete them. A screenshot is attached (see upper right corner). Thanks.

Without explanation or my consent, Firefox will occasionally download a .htm file into Downloads in the browser. Today it was WjZ510Su.htm This has been happening randomly for a few months. What are these files? Without knowing what they are, I always delete them. A screenshot is attached (see upper right corner). Thanks.
Attached screenshots

All Replies (3)

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Do those files have a file size of zero bytes? Have you been downloading another file when this happens?

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A recent one was 5.1MB. I'm not downloading anything when it happens. It occurs when I'm just browsing the internet, seems like it MAY happen on 1 particular website that I go to every day. I did run Malwarebytes on one of them, and nothing bad was found. But I delete them anyway.

Any ideas? Since they have the Firefox logo, it seems Mozilla would be able to explain what they are. Thanks.

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Did you check the content in a text or hex viewing utility to see what is in the file ?