Customize Line Chart Appearance Based on Column Values (e.g., Highlight Offending Data Points)

What is the problem or goal the end user is trying to solve or accomplish?

The user wants to highlight specific data points on a line chart based on a boolean column, such as is_offending. The goal is to visually emphasize anomalies or important events along a time series—e.g., by changing the background color or data point styling—making them easier to detect during analysis.

How are they solving it currently?

Currently, users are employing a workaround using a Mixed Chart:

• Plotting is_offending as a secondary bar chart (0/1 values) behind the line.

• Making the y-axis for the bars invisible.

• Using transparency to simulate a background highlight.

• Using “Step - middle” for interpolation to align the bars cleanly.
  However, this workaround is clunky, not intuitive, and requires visual compromises (e.g., cannot completely hide the secondary chart).

What is the recommended solution by the Customer?

Ideally, users would like to:

• Apply background highlighting in specific x-axis regions where is_offending is true.

• Alternatively, style specific data points or line segments conditionally (e.g., change point color, size, or shape) based on column values.

• Support multiple metrics in one chart with conditional styling based on shared metadata columns like is_offending.