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Hey Team, My new FF version not supporting MHT Files, Older version is good and it opens MHT files when i drag and drop the mht file in FF browser. Please help

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  • Last reply by jscher2000 - Support Volunteer

Hey Team, Good day!

My new FF version not supporting MHT Files, Older version is good and it opens MHT files when i drag and drop the mht file in FF browser. But in new FF browser it is giveing error and moreover there is no UNMHT Add on in the extension.

This is very critical and important for me.

Please help

Hey Team, Good day! My new FF version not supporting MHT Files, Older version is good and it opens MHT files when i drag and drop the mht file in FF browser. But in new FF browser it is giveing error and moreover there is no UNMHT Add on in the extension. This is very critical and important for me. Please help

All Replies (3)

Separate Security Issue, please update your Flash 28.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html If you use it Reinstall with Flash Player Version: 30.0.0.154 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

Hi, these programs open MHT files. Please start opening and converting them for use with Firefox.

Am Using MacBook Air. the process you mentioned is not working for me

Firefox never had a feature to open MHT files on its own, but that was added by one or two legacy extensions. Firefox 57+ can no longer run legacy extensions, and I don't know of any new extensions that can read MHT.

Also, I don't know of any programs for Mac that open MHT files, other than maybe Microsoft Word.

But I saw a tip on a Mac site to change the .mht file extension to .eml so that Apple Mail or your default email program opens the file. The reason is that apparently MHT is the same encoding as EML.