The letter i is not displayed properly.

Question

I've been meaning to post about this for a while. On my machine (LMDE, firefox, various versions) the letter i on AU is not displayed properly:

                                                                        

You will need to zoom in a bit to see it clearly, but the i looks like this:

                                                                                

This is surprisingly annoying and makes the text harder to read. For example:

Oddly enough, the letter is displayed correctly aligned if I increase the magnification of the page but it is off kilter at the default zoom level. It also looks OK on chrome, so it looks like a firefox-specific issue. It is also an AU-specific problem; I frequent quite a few SE sites and only have this issue here. I am guessing that this is because I am not using Ubuntu and this is some kind of Ubuntu-specific font but can this be fixed please?

Answer 1

Turns out Mateo was spot on. The issue was fixed by adding this to my ~/.config/fontconfig/fonts.conf file (not ~/fonts.conf, when that file was created, running fc-list returned an error message telling me that I should switch to the one in ~/.config because ~/.fonts.conf is deprecated):

<match target="font">
    <edit mode="assign" name="autohint">
        <bool>true</bool>
    </edit>
</match>

My entire ~/.config/fontconfig/fonts.conf file is:

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
 <match target="font" >
  <edit mode="assign" name="autohint">
     <bool>true</bool>
  </edit>
</match>
 <match target="font" >
  <edit mode="assign" name="rgba" >
   <const>none</const>
  </edit>
 </match>
 <match target="font" >
  <edit mode="assign" name="hinting" >
   <bool>true</bool>
  </edit>
 </match>
 <match target="font" >
  <edit mode="assign" name="hintstyle" >
   <const>hintfull</const>
  </edit>
 </match>
 <match target="font" >
  <edit mode="assign" name="antialias" >
   <bool>true</bool>
  </edit>
 </match>
</fontconfig>

I can now see the i with its dot in the right place. The dot was tiny however until I changed hintslight

Answer 2

Try this: https://askubuntu.com/a/362643/47291 , since it seems Firefox dosn't detect the system settings, Except for "hintstyle" use hintslight

I believe this happens because the "i" actually has a round dot on top, and the subpixel hinting is hinting on that edge while the other part of i falls where it doesn’t get hinting on that edge. Chrome might be respecting system settings or using different values for this.