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How Can I Detect Whether the User's Firefox Supports MHTML?

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  • Last reply by mikek1965

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Is there a browser capability property that I could look at to detect whether the user's version of Firefox (including, for instance, an "unMHT" add-on) supports MHTML? Currently we provide reports to our users in this format and want to provide a link to add-on's in case the user cannot actually view the format; but show the report if the add-on or capability is present.

Is there a browser capability property that I could look at to detect whether the user's version of Firefox (including, for instance, an "unMHT" add-on) supports MHTML? Currently we provide reports to our users in this format and want to provide a link to add-on's in case the user cannot actually view the format; but show the report if the add-on or capability is present.

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Sorry, you can't detect if a user has unMHT installed.

Have you tested your MHTML files with Firefox and unMHT?
MHTML was never adopted as an official standard by W3C - http://en.wikipedia.org/wiki/MHTML - and from my limited usage of unMHT, it isn't exactly the same as what MS uses with IE. I have had problems displaying a file saved in one browser in another brand browser, and don't remember the specifics beyond IE8 won't correctly display unMHT files even when the file extension is changed from MHT to MHTML. Plus there's a 2nd add-on / extension - Mozilla Archive Format - that some users may have installed for MHTML files.

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I am testing right now and it doesn't look too good. What I can pull down in IE8 just fine comes up almost completely blank in Firefox 9 with unMHT installed. It sounds like the whole standard is flaky. We may have to stick with our original plan of just offering PDF to non-IE users.