> When you write software, you test it on every platform you choose to support. This depends on your definition of "support". It's very likely that Microsoft d

> When you write software, you test it on every platform you choose to support. This depends on your definition of "support". It's very likely that Microsoft do not claim to support (as in, put customer support resources behind) Firefox Nightly, this would be reasonable as it's provided for development utility, not daily use. However, I do somewhat disagree that you test it on every platform. If Teams is built as a website, do we expect them to test every feature of every release on every browser? Probably not, we expect that they do reasonable testing across a representative range of browsers, maybe focused on major features.