[Lens] XY - Dragging a 2nd+ text field to workspace creates multi field

[ghudgins]

Describe the feature:
Dragging a second+ text field to workspace creates multi field

Describe a specific use case for the feature:
XY
Given I have a time series bar (XY) chart with a "Break down by" configured
When I drag another text field to the workspace
I need to create a multi field
So I can easily see the combination of multiple fields on the fly without having to drag all the way to the "Combine" option on the break down by

Cases to watch for / not change

• Dragging a 2nd+ number field will still go to a metric axis
• Dragging a 2nd+ string field to a table workspace should continue to nest the terms (shows up as rows)
• Dragging a 2nd+ string field to donut/treemap should continue to nest terms up to 3 and then disallow dropping

[elasticmachine]

Pinging @elastic/kibana-vis-editors @elastic/kibana-vis-editors-external (Team:VisEditors)

[flash1293]

I think we discussed something like this when talking about the multi field terms in the first place and back then we didn't want to make it too easy to hit this feature because of performance reasons as multi field terms might perform worse than regular terms. What about holding off this change and wait for a minor to see whether we run into issues with the existing multi fields integration?

If we are worried about the specific flow of a user continuing to drag fields into the xy chart, what about switching to table for this interaction for additional string fields as a safe band aid?

[ghudgins]

What about holding off this change and wait for a minor to see whether we run into issues with the existing multi fields integration?

Sounds good.

[ghudgins]

closing this. will re-open (and track via performance meta) if we decide we want it.