Feature request: allow renaming of insight series by breakdown

[abigailbramble]

Feature request

Is your feature request related to a problem?

If I create a basic insight for Pageview broken down by Browser, I then get a number of rows in my detailed results (as expected).

If I click on any of the pencils in the detailed results rows, I might assume that this would rename the row for me, but it is there to rename the series.

When I rename it (as we expect) it renames the whole series which affects all rows of that table (since I only have one series). This is clearly not the result that a user was expecting - and I can see their point.

Essentially, if a user wants to have different names for each row in the detailed results, currently they would need that many individual series with individual names.

We should consider allowing the renaming of the individual rows where the series is broken down by one or more filters.

Additional context

https://posthog.slack.com/archives/C011L071P8U/p1726566938934689

Debug info

No response

[annaszell]

Similar request here: #22242