Update Firefox data for Element API (#7205)
Update Firefox data for Element API (#7205)

This commit updates and/or corrects the Firefox data for the Element
API based upon results from the mdn-bcd-collector project (using
results from Firefox 1-82). The updates include mirroring of data and
notes to Firefox Android, as well as updating a few notes for
accuracy.
chrisdavidmills/browser-compat-data,chrisdavidmills/browser-compat-data,mdn/browser-compat-data,mdn/browser-compat-data