ROI editor 'Fill tool stopped working

Hi all, the 'Fill tool suddenly stopped working. All the other features are working well on ROI editor. Do you have any recommendation to tackle that?

Thank you!

I can reproduce this issue with MRtrix 3.0.8 on macOS 27.0.1 (26A434).

What MRtrix version are you using?

What OS are you using? And what version?

Problem diagnosed and fixed in mrview: Fix fill tool texture format in ROI editor by bjeurissen · Pull Request #3451 · MRtrix3/mrtrix3 · GitHub . If you are comfortable building from source you can check out the fix_roi_fill_format branch and build to fix.