Bugzilla

1) What questions will you answer with this data?
I'd like to use this data to better understand how users customize Firefox's high-contrast mode (HCM). This data will help the CSS working group make informed decisions about color-affecting media queries like prefers-contrast and forced-colors. My immediate use for this information is to compute the contrast ratio of each user-adjusted color pair, and use that to decide if user populations we plan to serve with prefers-contrast:high and prefers-contrast:low are accurate. Also, I'd like to see how many users fall in the "in between" area to know if we should argue for/against a generic "forced" value for prefers-contrast :) 

2) Why does Mozilla need to answer these questions?  Are there benefits for users? Do we need this information to address product or business requirements? 
Yes there are benefits for users! This data will ultimately ensure that media queries that could benefit HCM users are applied correctly (ie. that everyone who could benefit from them gets them, and that those who might prefer unmodified content get that instead). This data will also help us take a substantiated standards position. 

3) What alternative methods did you consider to answer these questions? Why were they not sufficient?
I've reached out to Microsoft to see what kind of information they have on HCM, since windows HCM is more common than firefox HCM (and affects all browsers). Their data was sufficient to answer questions like "what kind of themes are most common among HCM users?" and "what contrast ratios do users experience if they select X theme?" but ultimately they did not have data on customization, which is info we can get through our local HCM. 

4) Can current instrumentation answer these questions?
No, we currently log if HCM is enabled, but we have no information on how a user chooses to customize their HCM (or even if they customize it at all). 

5) List all proposed measurements and indicate the category of data collection for each measurement, using the [Firefox data collection categories](https://wiki.mozilla.org/Firefox/Data_Collection) found on the Mozilla wiki.   
I'm not sure if this is technically 1 or 2, but I'm leaning 2 since its a customization. 
<table>
  <tr>
    <td>Measurement Description</td>
    <td>Data Collection Category</td>
    <td>Tracking Bug #</td>
  </tr>
  <tr>
    <td>Foreground Color</td>
    <td>Category 2</td>
    <td>1694717</td>
  </tr>
<tr>
    <td>Background Color</td>
    <td>Category 2</td>
    <td>1694717</td>
  </tr>
</table>

6) Please provide a link to the documentation for this data collection which describes the ultimate data set in a public, complete, and accurate way.
This collection is documented in its definitions files Histograms.json, Scalars.yaml, and/or Events.yaml and in the Probe Dictionary at https://probes.telemetry.mozilla.org.

7) How long will this data be collected?  Choose one of the following:

* I want to permanently monitor this data. (Morgan Rae Reschenberg)

8) What populations will you measure?

* Which release channels?
All
* Which countries?
All
* Which locales?
All
* Any other filters?  Please describe in detail below.
N/A
9) If this data collection is default on, what is the opt-out mechanism for users?
Standard telemetry opt-out
10) Please provide a general description of how you will analyze this data.
Compute the contrast ratio between a user's foreground and background color using the standard definition here https://www.w3.org/TR/WCAG20/#contrast-ratiodef

11) Where do you intend to share the results of your analysis?
Locally among the accessibility team, and in summary with the CSSWG

12) Is there a third-party tool (i.e. not Telemetry) that you are proposing to use for this data collection? If so:
N/A

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