Axis Label Font Size Configuration Not Available

[madankgit]

Bug description

Superset currently does not provide a chart-level option to configure the font size of X-axis and Y-axis labels. Although theme-level configurations and ECharts overrides exist, they do not consistently apply or work as expected across charts, making them unreliable for controlling axis label font sizes.

This limitation restricts fine-grained visual customization and impacts readability, especially for dashboards with varied layouts, screen sizes, and chart densities.

Suggested Enhancement

Introduce a chart-level configuration option to control axis label font size for applicable chart types (particularly ECharts-based charts). This would allow users to adjust font sizes per visualization without depending on global theme settings.

Current Limitation

• Plugin-level customization is not feasible with the official Superset Docker image
• Theme-level overrides do not consistently work across charts
• Users lack per-chart control over axis label readability
• Common use cases such as large screens, dense dashboards, and presentations are impacted

Chart-Specific Overrides:

{
  "token": {
    "colorPrimary": "#2893B3"
  },
  "echarts_timeseries": {
    "xAxis": {
      "axisLabel": {
        "rotate": 45,
        "fontSize": 26
      }
    }
  }
}

Expected Outcome

Users should be able to configure X-axis and Y-axis label font sizes at the chart level using standard Superset installations, including the official Docker image.

Screenshots/recordings

No response

Superset version

6.0.0

Python version

3.9

Node version

16

Browser

Chrome

Additional context

No response

Checklist

• I have searched Superset docs and Slack and didn't find a solution to my problem.
• I have searched the GitHub issue tracker and didn't find a similar bug report.
• I have checked Superset's logs for errors and if I found a relevant Python stacktrace, I included it here as text in the "additional context" section.