Insomnia does not recognise JSON field names containing hyphens

Am using Insomnia version 2021.5.3. I’ve been setting up tags from previous responses which works fine. I’ve noticed that field names containing hyphens are rejected. For example my response contains a json field “task-id”, trying to reference it with “$.task-id” gives an error “Invalid JSONPath query: $.task-id”.
I’ve tried it on the latest version of Insomnia (v9.2.0) and it appears to work ok. Unfortunately I’m stuck with using 2021.5.3.
Is this an issue in 2021.5.3? Is there a workaround? If its an issue, does anyone know in which version it was fixed.