Bug: Legend changes to "(Blank)" when Initial Scroll Position is set to End

Hi,

I believe I have found a bug related to the new Initial Scroll Position setting on the X-axis.

Environment

• Power BI Desktop 2.158.1177.0 (64-bit)
• Power BI Service (app.powerbi.com)

Steps to reproduce

1. Create a stacked column chart.
2. Add a categorical field to the Legend (e.g. A, B, C, D).
3. Configure the visual so that a horizontal scrollbar appears (for example, by increasing the Minimum category width).
4. Set X-axis > Presentation > Initial Scroll Position = End.
5. Verify that the legend displays correctly.
6. Go to Data colors or Labels and modify one of the legend categories.
7. The legend immediately becomes "(Blank)" and the category names are no longer recognized.

Expected behavior

• The legend should continue showing the actual category names.
• It should remain possible to customize colors and formatting for each legend category.

Actual behavior

• The legend changes to "(Blank)".
• The categories disappear from the formatting pane.
• Individual color customization is no longer available.
• The visual itself still renders correctly, but any formatting option related to the legend field appears to be broken (data colors, labels, category-specific formatting, etc.).

Additional observations

• I can reproduce the issue in a brand new PBIX file using a simple sample dataset.
• The issue only occurs when Initial Scroll Position = End.
• If Initial Scroll Position = Start, everything works correctly.
• The problem is triggered after changing a category color or modifying category-specific formatting.
• The issue is reproducible in both Power BI Desktop and the Power BI Service.

Has anyone else experienced this issue?

Thanks.