1679878 - Media Queries no longer work in HTML emails

Status: RESOLVED DUPLICATE of bug 1659362

(Thunderbird :: Untriaged, defect)

Description

[Remi]

Attachment: media-queries-removed.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:84.0) Gecko/20100101 Firefox/84.0

Steps to reproduce:

1. Get HTML code at https://www.caniemail.com/tests/css-media.html
2. Send the HTML to your inbox (using for example a test service like Putsmail.com)
3. Open email in Thunderbird 78.5.0

Actual results:

Every test line in the email appears in red, indicating that media queries are not supported. Inspecting the email with the developer tools show that all media queries styles have been removed. (See attachment media-queries-removed.png).

Expected results:

Relevant test line should have appeared in green. Inspecting the email with the developer tools should show all media queries.

Comment 1

[Magnus Melin [:mkmelin]]

There's a pref you can set to enable them.

Comment 2

[Remi]

Does that mean that we should consider Thunderbird no longer support media queries by default?

Also, for those interested, I've been able to enable them locally by adding a user.js file in my ~/Library/Thunderbird/profiles/example.default/ with the following content:

user_pref("mail.html_sanitize.drop_conditional_css", false);

Comment 3

[Magnus Melin [:mkmelin]]

At the moment it requires setting that pref yes. I've proposed we don't do don't set that by default.
(You don't need a user.js file, all it takes is going to the config editor.)

Comment 4

[Remi]

Thanks for your answer! (I've used a user.js file because I haven't been able to find the config editor. I found your other post linking to http://kb.mozillazine.org/Modify_Thunderbird_settings but I can't even find the Tools > Options menu on macOS 11.)

Comment 5

[Magnus Melin [:mkmelin]]

On Mac/Linux it's Edit | Preferences. Then user the search box in there if you don't see it.