Version

5.5.1

Link to Minimal Reproduction

https://jsfiddle.net/sd807pz3/1/

Steps to Reproduce

1. create a pie chart using "svg" rendered and "outside" labels
2. call echartsInstance.getDataURL()

Current Behavior

Error TypeError: Cannot read properties of null (reading 'length')

Expected Behavior

Get base64 data.

Environment

- OS:
- Browser:
- Framework:

Any additional comments?

Changing the rendered to "canvas" or the label position to "outside" returns base 64 without error.