eaf-open-mail-as-html doesn't display embedded images that are attachments

[Jdogzz]

Describe the bug
When the html version of an email incorporates pictures that are attachments in the email, the eaf-open-mail-as-html view only displays broken image areas for those pictures.

To Reproduce

1. Open email with inline images that are attachments.
2. Call eaf-open-mail-as-html

Expected behavior
It will display all images correctly in the html view.

Versions (please complete the following info):

• Distro and DE/WM: Turnkey Core 16.0 and Xpra
• Versions of Dependencies:
• • python-pyqt5: 5.11.3+dfsg-1+b3
• • python-dbus: 1.2.8-3
• • python-pyqtwebengine: 5.11.3+dfsg-1+b3
• M-x emacs-version: GNU Emacs 26.1 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw3d scroll bars) of 2019-09-23, modified by Debian

Screenshots

Additional context
Add any other context about the problem here.

[manateelazycat]

Can you give us a minimum reproduction step or sample mail?

I'm not use Emacs read mail, can't test this issue.

[Jdogzz]

I made an example email in gmail and it too can produce the problem described above.

test.zip

[MatthewZMD]

I know this issue, it's not very easy to solve at the moment.

[Jdogzz]

I've been reading through the code, would it not be sufficient to extract all images to the /tmp dir (looks like this is what I have set for temporary-file-directory) before it packages up the html file for display?

I did try extracting the images there before calling M-x e-ht but it didn't fix the problem. I noticed I couldn't even find the html file it created at the location shown in the minibuffer so I'm guessing there is more processing going on, maybe part of what you mean by it not being easy to solve.