You are not the first to observe this minor cosmetic bug. This early within the iPadOS 26 lifecycle, you will likely encounter various minor (and perhaps not so minor) issues.
You would be best advised to submit a Bug Report via Apple's Product Feedback portal. For iPad and iPadOS:
Feedback - iPad - Apple
When submitting your Bug Report, please ensure that you include your iPad model and the installed version of iPadOS within the body-text of your report - along with full details of the problem. Do not rely upon the pick-list alone - as this rarely includes the current version of iPadOS.
Every Bug Report counts. Unless reports are submitted (with adequate detail), Apple may not assign resources to investigate and correct the issue.
In addition [i.e., not as a substitute] to submitting a Bug Report, you might also consider reporting the problem directly to Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page; you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:
https://apps.apple.com/app/apple-support/id1130498044