I found a bug in Dashboard views, when a table view in that dashboard has blanks in the ‘group by’ column.
Clicking to expand/collapse the grouped rows will stop working when one of the groups is ‘blank’.
https://my.pcloud.com/publink/show?code=XZ0jfi7ZBODHhml3Iy0mB1GkzADJUmoUoOWX
Tested on MacOS/Chrome.