.mht web page archive does not show url link

I’m not sure whether to post a community question or a bug report. The last q about .mht was in 2009!
Any experience with this issue would be helpful. Does everybody use Safari? Is this a common use-case (surely it must be if I’ve hit it on Day 1…)


DEVONThink Version 2.7.3.
Mac OS X 10.9.5.

Steps to repro:

Install unMHT for Quicklook from unmht.org per instructions.
Using Firefox install the “Mozilla Archive Format” add-on.
Using Firefox save a webpage as .mht format archive.
Drag from Finder to inbox in DEVONThink.

Expected Results:

DEVONThnk shows a preview of the page. Yes - this works
DEVONThink shows a url link above the preview (see attachment)

Actual Result:

No url link


Using Safari I can save a .webarchive and drag it from Finder into DEVONThink. DEVONThink reads the url and provides a click-able link.

However I use Firefox extensively as I’m multi-platform and need to sync across machines and OS.

There are Firefox plugins which allow to save as .mht or .maff archive format. DEVONThink doesn’t recognise .maff at all. However it does recognise .mht, and with the addition of unMHT for Quicklook/Spotlight (unmht.org) it will show a preview. Nice.

However DEVONThink doesn’t seem to be able to extract the Url from the archive to show a click-able link. This is critical as otherwise I can’t get back to the original website.

If you look at the extended file attributes for .mht files you’ll see that they are missing the attribute that contains the “where from” URL of the original web source, whereas .webarchives contain this value. I assume this is what DEVONthink is looking at for source URL.

I’d suggest you would want to ask Mozilla and/or the developer of unMHT what can be done about this, since it’s probably not a DEVONthink issue, but an issue with the file itself. DEVONthink merely uses QuickLook generators when they are provided (same as what Finder does). As you know, Firefox/OSX compatability is not always robust.

I don’t use Firefox myself, but is there any reason why you cannot install the DEVONthink extension for Firefox and capture pages as a Web Archive?

Thanks for your response Korm.

I think I (hopefully politely) disagree.

The .mht format has within it a “Content-Location” field that contains the source url. See http://www.fileformat.info/format/mime-html/spec/index.htm

Extended attributes is a unix thing originally so inherited by linux and BSD (and thence Mac OS X). As far as I can discover they are not widely used.

I’d argue that if you’re going to support the format then you would ideally support it according to the spec, and not make use of platform-specific features. That way, a growing number of cross-platform Mac users like me :slight_smile: would get a friction-free experience.

So the bug is that DEVONThink doesn’t correctly support the .mht standard in respect of the Content-Location field, and therefore fails to provide links back to an original page from a .mht web archive.

Thanks for making me investigate this a bit further. I hope its helpful to the Dt folk.


@Greg Perfect! Thanks.

That’s what I wanted all along, but couldn’t find it…

For anybody else with the same issue in another 4 years time, the extension isn’t in the Firefox catalog, but can be found by a judicious Googling with Bing.

On the Dt site it’s actually on the Downloads page under the link “Extras and manuals” which is easily missed:

Thanks again


The Clip to DEVONthink extension can also be installed in Firefox via the Install Add-Ons procedure (which should be run after every update of DEVONthink).

The next maintenance release will improve the compatibility to third-party Spotlight plugins like unMHT.