I checked it in my environment and got the same result (will check with UI team whether this is a known issue with the new client or not). For sure need to be fixed ASAP.
For singular variable, could you try to 'expand' it by clicking on the 'greater than' sign on the left of the variable name? It should display all of the variable's properties; hopefully the name will be readable there.
As for array variables - you can actually edit the items in the list, if you click on the variable name, and in the shown dialog select the checkboxes on the left of the items. The hard part is to figure out which of the items are the ones you want to edit when all of them look the same [object type]