MHT files

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MHT files

Post by fugue » 2016-01-27, 00:07

This may be related to the similar .maff file issue, posted just below.

After upgrading to 26 can not open .mht files with Palemoon.
(I use them constantly, all day, so need the capability)
Worked fine with 25.

Have both the 'Mozilla Archive Format' (3.1.1) extension, and 'unMHT' (older version compat. with PM) installed...specifically for .mht files.

Edit: Found that Palemoon 26 will still save .mht files. But will not open them.


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Re: MHT files

Post by joe04 » 2016-01-28, 19:13

yep exact same problem as viewtopic.php?f=16&t=10843 (doesn't matter if mht or maff files)

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Re: MHT files

Post by davews » 2016-01-30, 11:19

I have long used .mht for page archiving and use unMHT with Palemoon. If as it seems this format won't work in PM26 then it is a show stopper for me and I will stay with 25.8.1. Moonchild, any thoughts on this issue?

Ex Pea

Got UnMHT working with Pale Moon 26

Post by Ex Pea » 2016-02-08, 19:35

I also experienced that UnMHT stopped opening .mht files when I upgraded to Pale Moon 26. I also depend heavily on this format.

I adapted the first technique described here: viewtopic.php?f=16&t=10843#p76343
and here: viewtopic.php?p=76370#p76370

I extracted the contents of my v7.3.0.5 UnMHT xpi installer (rename to. zip, extract with an unzipper), searched for all occurances of "Gecko-Content-Viewers" and replaced with "Goanna-Content-Viewers". This affected three files:

I put these modified files back into the zip, renamed back to xpi, uninstalled UnMHT, installed this modified version...and I can once again open .mht files in Pale Moon.

I didn't need the second technique, regarding getting the Save functionality to work, since this didn't break for UnMHT.

Good luck to all.


Re: MHT files

Post by Andys » 2016-02-15, 10:22

So, erm, i'd like to hear Palemoon dev's opinion on this problem.
Will there be a compatible version of this addon on
Because I am not very inclined to modify and 'sideload' xpi, since that effectively blocks future addon updates.

Maybe make a 'compatibility mode' in PM, for these problematic addons, which will supply old engine description to them?

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Re: MHT files

Post by back2themoon » 2016-02-15, 12:28

Andys wrote:So, erm, i'd like to hear Palemoon dev's opinion on this problem.
Will there be a compatible version of this addon on ... zarchiver/

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Re: MHT files

Post by Ghostwalker » 2016-03-04, 01:05

Just some feedback on my adventures with unMHT and MozArchiver. On my Pale Moon 26.1.1 (x86) MozArchiver is excellent of course,
the only thing is for my needs the "Save selection as MHT..." context menu function of unMHT is necessary for saving just the pertinent info off a page.
Using Ex Pea's adaptation here:

And just for fun inserting Pale Moon's GUID into the install.rdf:
<!-- Pale Moon -->

All went well using the newest unMHT .xpi that works with PM 26.1.1:

The other techniques were in fact not necessary for me either and possibly not the PM GUID either.
Tried both unMHT and MozArchiver together, with one then the other and both will save and open .mht files sucessfully.
The .maff and .mht conversion to each other function of MozArchiver is very handy.
Using the PageZipper add-on you can load all pages of a post and save them in a single .mht or .maff.

For some of you who are understandably shy to experiment on a production machine, a possible solution to these necessary growing pains is to have multiple
profiles and run one as i.e. "standard" and others as test1, test2, etc. and just have some profile(s) committed to test add-ons, a profile strictly for saving pages,
one just for plugins you do not want to update, for security testing etc. Just make a PM shortcut somewhere and in the target box add a space then -p like:
"C:\Program Files (x86)\Pale Moon\palemoon.exe" -p

For Linux you can right click the desktop, choose:
Create Launcher > choose a Name: > Command: palemoon -p -no-remote
Under Permissions select: Allow this file to run as a program
Search for icon, try: /opt/palemoon/browser/icons/

When launching, unselect: Don't ask at startup
The ProfileSwitcher add-on will open any profile concurrently with another.
Hope this helps. PM 26.1.1 has really resolved many things now, Thanks MC and team. :thumbup: