Garmin Connect Web not showing negative values for IQ data chart

The Garmin Connect Web view for an activity no longer shows the chart for an IQ data field correctly - any negative values are not plotted and are missing from the chart. This is a new bug: it used to work correctly up to a week or so ago. It still works correctly in Garmin Connect Android App.

Here is the web view (negative values are missing)

Here is the android app view (negative values are shown correctly)

For information: the IQ app is the "Readable R&T Pacer" Data Field by developer HrMortensen