Upgrade to v7.0, cannot find column style option

Hi, I have updated grafana to v7.0 this morning and I faced a problem that, I used to query to table and it has mix value number and string, I used to have able to format some column as string (text format) but after updated to v7.0, I am no longer find the option column style or unit as text anymore?

Can someone show me how can I find that again?

I am also experiencing this issue if anyone has a solution.

Looks like column styles are being implemented, perhaps included in v7.1: https://github.com/grafana/grafana/issues/24482