OWD project: Fix errors in BCD for API, CSS and JS going back to at least 2020

[foolip]

#66 and similar efforts in the past have eliminated all true and null values in BCD for API, CSS and JS data. @queengooborg and I used https://mdn-bcd-collector.gooborg.com/ to finish the API data over the course of 2021, and the collector also covers a lot of CSS and JS.

We have found that comparing BCD to feature detection results invariably finds a lot of errors in BCD. By comparing BCD with the collector results, we can find many false positives and false negatives. This will likely lead to many features looking "better" (more green) as support has shipped in the past 2 years but BCD was never updated.

Such cross-checking can in principle go back over 10 years, but I suggest limiting it to browser releases after 2020-01-01, and updating earlier data only when it's really easy and does not require much digging to verify.

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For reviewers, here's a link to the guide on how to review collector PRs: https://github.com/GooborgStudios/mdn-bcd-collector#reviewing-bcd-changes

[foolip]

@queengooborg @robnyman do you have permissions to label this as a proposal for Q3 planning?

[queengooborg]

I have a feeling that this will span across both Q3 and Q4 for how big the project is. Maybe we should separate this into three projects, one for each category?

[teoli2003]

I have a feeling that this will span across both Q3 and Q4 for how big the project is. Maybe we should separate this into three projects, one for each category?

Yes, I think having smaller projects is a good thing here. This helps get focused and claiming victories is always a good feeling and a good way to communicate progress.

[foolip]

I think an important first step here is to list all of the contradictions between BCD and collector data for the past two years' releases. There is no script for this currently.

[Elchi3]

Thanks for filing this OWD project proposal!
I think this proposal is specific and actionable. We need to determine the priority relative to all other projects, though.

The OWD prioritization criteria guides us to make decisions.
Please complete and/or correct the following, so we can judge the priority correctly here.

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Effort

It seem like there is some scripting needed to determine the contradictions between BCD and the collector.
This will likely produce a list of some easy cases and cases where it is unclear what is correct. It probably requires expert knowledge to make the correct calls. The above comments suggest that this project could be split into parts to lower that workload.

Dependencies

• Knowledge about BCD and the collector.
• A script to list contradictions
• Knowledge how to decide what is correct.

Community enablement

Correct me if I'm wrong but dealing with the contradictions is hard. Not sure how much we will be able to involve the community with this project.

Momentum

Seems like correct compat data is of interest for current initiatives like Interop?

Enabling learners

n/a
Not part of any curriculum or learning pathway.

Enabling professionals

n/a

Underrepresented topics / ethical web

n/a

Operational necessities

n/a

Addressing needs of the Web industry

Interop?

[Elchi3]

In yesterday's planning call, @queengooborg said:

• It probably makes sense to have different tasks for different content areas here (CSS, JS, APIs)
• Vinyl reckons this is mostly done for Web APIs already.

Assigning this to @queengooborg to post an initial assessment of what work is required here and whether we want this project to be split up which would then allow us to prioritize say CSS data over other data.