US nonprofits are as transparent as can get. Their tax returns have to be public record by law. Maybe a press release shared to Hacker News doesn't have the information you want, but you can call them up any time you please and get a detailed categorized line items of everything they spend money on, or use any number of aggregator services that publish IRS Form-990s for free on the web. You can also get it directly from the IRS itself, which has a searchable database. Here is Mozilla's tax return for 2024: https://apps.irs.gov/pub/epostcard/cor/200097189_202412_990_...