Acid Tests on Thunderbird
April 29th, 2009 Posted in Mozilla, ThunderbirdRobert’s recent post about the acid tests on wikipedia reminded me that I’ve been meaning to post about Thunderbird and the acid tests for a few months now.
Sometime last year there was a discussion on the results of Acid tests in Thunderbird. Whilst Acid3 was a similar result to the equivalent Firefox build, Acid2 was much worse – this was strange given that Thunderbird runs on virtually the same Gecko engine that Firefox does.
A bug was duly filed, after a bit of investigation, it was found that there were two issues: 1) Thunderbird denied access to load data URIs, 2) Thunderbird needed plugins enabling (plugin loading is disabled by default to help protect users against detection of reading by loading remote data, and potentially other reasons I don’t know about at this time).
We then fixed the content policy so that we enabled the data URIs. Using today’s nightly builds (Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1b5pre) Gecko/20090429...), here is Acid 2 in Firefox (left) and Thunderbird (right):
Additionally Thunderbird passes the Acid 3 test to very nearly the same extent as Firefox:
The difference here is the “Linktest Failed” – as Thunderbird isn’t a browser, we don’t enable history on links (they don’t turn a different colour when you click on them). You can see this effect of the “Linktest Failed” in Firefox’s private browsing mode.
For both these tests, all I changed from the default set up was to set the preference mailnews.message_display.allow.plugins to true. To load the web page, I set Thunderbird’s start page to the appropriate Acid 2 or Acid 3 URL and then selected Go -> Mail Start Page.
This is both good for Thunderbird – basing ourselves on Gecko means we don’t have to worry too much about laying out what we display – and for extensions – authors can know they can load pages/render content in Thunderbird and they will come out the same as Firefox.
6 Responses to “Acid Tests on Thunderbird”
By Gus Richter on May 4, 2009
This is, of course, ‘only’ for authoring the Mail Start Page and/or for Extensions and thereby the developers are well served.
For the authoring of actual Mail content, which is the raison d’être for Thunderbird, Acid2 and Acid3 show how Thunderbird is crippled for users. Try sending them to yourself in mail.
By Standard8 on May 4, 2009
@Gus:
I disagree. Acid2 isn’t crippled at all – as long as you have enabled plugins as I said originally.
Acid3 is crippled but only because we block Javascript for security reasons. All the other non-javascript reliant layout functions etc we can display to the same capability as Firefox.
By Gus Richter on May 5, 2009
I have just sent myself Acid2 Test using:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1b5pre) Gecko/20090504 Shredder/3.0b3pre
I also have changed in about:config
mailnews.message_display.allow.plugins;true
The smiley is practically unrecognizable.
I suggest that you try mailing Acid2 to yourself just as I did and you will encounter a problem right away in that you will not be able to place the stylesheet into the head section without an addon providing the head access. You can cheat by placing it into the body section which works although not conforming.
I have also sent the same as a test to:
mozilla.test.multimedia
newsgroup. It hasn’t shown up yet because there is a single moderator that approves all. Hopefully sometime later today it will be available. It’s titled:
Acid2 test for Shredder
If you wish I’ll send it to you if you provide me with your address.
Acid3 is for another time.
By alta on May 5, 2009
curious as to how you got the Acid3 page to show for that screenshot, given that js is ‘disabled’..
By JoeS on May 6, 2009
Acid tests running in the “start page” or in an iframe really mean nothing as to how TB relates to web style content. After all is said and done Gecko can only render the content that is presented to it as streamed through LibMime. Our support for CSS styles is way back there in the dark ages. Because somebody decided that it had no place in mailnews. And that is the conundrum that we face in bringing TB into the mainstream of “how people want to communicate” today.
IMHO we must be part of the Web culture, or TB will die. Here’s an example:
https://bugzilla.mozilla.org/show_bug.cgi?id=154836
That doesn’t show much “compliance” with today’s common usage.
By Standard8 on May 6, 2009
@alta: I was quite clear in my original description that I used the mail start page.
@Gus & JoeS: Yes we have issues with CSS and some display items, but the point is the capability is there, even if its not fully enabled – it is something I expect we’ll be looking at in future versions. It is also something we don’t have to manage – we get it for free from core.
For extensions the capability is definitely good news – they can try out new things that they may have thought was only possible in Firefox.