When reviewing the History sidebar, you may occasionally notice yellow warning symbols beside certain steps. Yellow warning messages may appear if you have missing or invalid results for a certain step. A few examples can include missing references for edges or faces.
You can quickly resolve common history warning symbols through the following steps:
Click/tap History to open the History sidebar.
Expand the card of the step with a warning symbol to see the error message.
Click/tap Fix.. beside the warning error message.
Select the missing entities or references in your model. Note: The missing references are usually highlighted in yellow.