306270 - Changing the Default Font can cause a sans-serif font to be used for Serif

Status: NEW

(Firefox :: Settings UI, defect)

Description

[Grey Nicholson (they/them)]

If the Proportional font is set to Serif and the user changes the Default Font
to Arial in Tools > Options > Content (i.e. without going into the Fonts &
Colours: Advanced dialogue), the Serif font becomes Arial.

To reproduce:
1. Tools > Options > Content
2. Set Default Font to Arial
3. Click Fonts & Colours: Advanced

Arial is now both the Serif font and the Sans-serif font.

Expected results: Change the Proportional font to Sans-serif; change the
Sans-serif font to Arial; leave the Serif font unchanged.

Comment 1

[Dave Townsend [:mossop]]

The default font style for web pages is serif. So changing the default font
changes the font used for the serif font.

I suspect this is invalid unless there is a plan to change the default font
style to be something else.

Comment 2

[Grey Nicholson (they/them)]

(In reply to comment #1)
> The default font style for web pages is serif. So changing the default font
> changes the font used for the serif font.

But the user wouldn't know this unless they opened the Advanced dialogue. They
would expect Arial to be used by default, but not when the page specifically
requests a serif font.

> I suspect this is invalid unless there is a plan to change the default font
> style to be something else.

This bug isn't about what the default font style is; it's about changing the
user's Proportional font style to accommodate their preferred default font,
instead of allowing nonsensical font assignments (such as Serif = Arial).

Comment 3

[Ria Klaassen (not reading all bugmail)]

Of course Arial and Verdana should not be in the Serif list. But a lot of people
would not understand that in order to get Verdana as your default font, you
first need to change Proportional to Sans Serif and subsequently Sans Serif to
Verdana.
I think that's why they put these Sans Serifs in the Serif list. If it is not
done on purpose, it is a "good" bug.

Comment 4

[Grey Nicholson (they/them)]

(In reply to comment #3)
> But a lot of people
> would not understand that in order to get Verdana as your default font, you
> first need to change Proportional to Sans Serif and subsequently Sans Serif to
> Verdana.

Yes, exactly. To be really clear, I'm suggesting that Firefox should do this by
itself when someone requests Verdana as their default font.

Comment 5

[Helder "Lthere" Magalhães]

(In reply to comment #1)
> The default font style for web pages is serif. So changing the default font
> changes the font used for the serif font.

Is this a Gecko limitation or part of any standard (I might not be aware of)?


> I suspect this is invalid unless there is a plan to change the default font
> style to be something else.

The use case would be allowing users selecting a simpler font for pages which don't force a specific style, while not breaking existing pages with custom font styling (set through generic font family names). For example, generally I don't like serif fonts much due to the glyph being more complex and harder to read than sans serif fonts. I also suspect there are performance differences, given the higher relative complexity of serif font glyphs.

I changed the default font but rolled back the change to save from potential style behavior breaking due to this -- incorrect IMO -- assumption (default font = default serif font).


Steps to reproduce:
1. Open "Font families" page [1] of W3C's CSS tips & tricks;
2. Look at "serif" item of "'serif': normal fonts with serifs";
3. Change default font to a sans-serif font (such as "Arial" or "Helvetica") using "Tools" menu, "Options..." option, "Content" tab;
4. Look at "serif" item of "'serif': normal fonts with serifs";

Expected results:
Text "The Quick Brown Fox Jumps Over The Lazy Dog" uses serif glyphs in both steps 2 and 4.

Actual results:
Text "The Quick Brown Fox Jumps Over The Lazy Dog" changes to sans-serif in step 4.

Workaround:
Go to "Tools" menu, "Options..." option, "Content" tab, "Advanced" button and, in the  change the "Prop


Confirmed with both stable [2] and nightly [3] builds on Windows.


[1] http://www.w3.org/Style/Examples/007/fonts
[2] Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.7) Gecko/2009021910 Firefox/3.0.7 (.NET CLR 3.5.30729)
[3] Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2a1pre) Gecko/20090313 Minefield/3.2a1pre

Comment 6

[Ross Grady]

I have a more basic use-case that is also, IMHO, broken, in the same way. (Ubuntu 8.10, Firefox 3.0.7). 

I wish to use sans-serif as my default font for text which does not specify *any* font face or family. I don't want to pick a specific typeface in Firefox, I just want my system default sans-serif.

So I go to Edit | Preferences | Content and in the "Default Font" drop-down, I select "sans-serif" instead of "serif." To my mind, this means "fonts that don't specify a face will now be sans-serif instead of serif." 

Curious about which font is currently specified as the browser default sans-serif font, I then click "Advanced" and see the following non-intuitive results:

Proportional: Serif
Serif: sans-serif
Sans-Serif: sans-serif
Monospace: monospace

Huh?? What I would *expect* to see would, rather, be the following:

Proportional: Sans-Serif
Serif: serif
Sans-Serif: sans-serif
Monospace: monospace

The plot thickens further. If I manually change the entries in the Advanced section to reflect the above, and exit, and then change the parent dialog's "default font" back to "serif," then the entries in the Advanced section now look like this:

Proportional: Sans-Serif
Serif: serif
Sans-Serif: serif
Monospace: monospace

In other words, it *appears* that what happens, from a user perspective, is that changing the "default font" on the top-level dialog does not change the value of "Proportional," but rather reads the value of "Proportional" and then goes and changes the value of whichever family is specified in "Proportional."

This leads, as documented above, to utterly non-sensical results.

I understand that there may be countervailing use-cases in which this behavior makes sense, but this case as presented is hardly an edge case.