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Why doesn't Firefox register .mht files on Windows?

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.mht and .mhtml files aren't registered when Firefox is installed.

.mht and .mhtml files aren't registered when Firefox is installed.

Chosen solution

By default Firefox doesn't render MHT or MHTML, so there aren't any registry strings or file associations set by the Firefox installer. You should be able to set those file associations yourself in the Control Panel.

There's also the UnMHT add-on for Firefox.
https://addons.mozilla.org/en-US/firefox/addon/unmht/

5 or 6 years ago when I tested both MAF and UnMHT, I found UnMHT to be a better add-on due to it producing more accurate MHT files - displayed better in IE8 than files saved by MAF, at that time.

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All Replies (4)

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You can look at this extension:

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Hi. I already have MAF installed. Was talking about the Windows file associations. I.e., clicking on a link in Explorer should open a .mht and .mhtml file by default.

Wasn't sure where to post this as a feature request.

Thanks for replying.

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Chosen Solution

By default Firefox doesn't render MHT or MHTML, so there aren't any registry strings or file associations set by the Firefox installer. You should be able to set those file associations yourself in the Control Panel.

There's also the UnMHT add-on for Firefox.
https://addons.mozilla.org/en-US/firefox/addon/unmht/

5 or 6 years ago when I tested both MAF and UnMHT, I found UnMHT to be a better add-on due to it producing more accurate MHT files - displayed better in IE8 than files saved by MAF, at that time.

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That makes sense. Thanks for informing me.

Much appreciated.