RLE segmentation mask visible in dataset thumbnail, but invisible in annotation preview/editor

在 Roboflow Web UI 中使用 arcade__000268.jpg 及其 RLE vessel 标注重现该问题。将数据集网格渲染器与标注/编辑器视图进行比较，然后验证掩码叠加层在两个视图中都可见，同时该标注仍列在左侧面板中。

Hi Roboflow team,

I’m seeing an issue with displaying segmentation masks encoded as RLE.

Problem

In the dataset grid / thumbnail view, the annotation mask is displayed correctly on top of the image.

However, after opening the same image in the annotation preview/editor, the mask is no longer visible. The annotation still exists in the left panel, but it is not rendered on the image.

Expected behavior

The RLE segmentation mask should be visible both:

1. in the dataset thumbnail/grid view,
2. and after opening the image in the annotation/editor view.

Actual behavior

The mask is visible in the thumbnail, but invisible in the opened image view/editor.

Example

In the dataset grid, the purple vessel mask is visible correctly:

arcade__000268.jpg

But after opening the same image, the annotation is listed as vessel, while the mask overlay is not visible on the image.

Screenshots

I attached two screenshots:

1. Dataset grid view — mask visible correctly.
2. Annotation/editor view — same image, mask invisible.

Dataset / annotation details

• Task type: instance/semantic segmentation
• Annotation class: vessel
• Mask format: RLE
• Example file: arcade__000268.jpg
• Browser/app: Roboflow web UI

Additional note

This looks like a rendering/display issue rather than a data issue, because the same mask is rendered correctly in the thumbnail view.

Could you please check whether RLE masks are handled differently in the dataset grid renderer and the annotation/editor renderer?

Thanks!