How do I hide this blue label with the element information from my project?

[tank666]

Unable to hide 'Contents' label on selected objects

This label appears when you set the Resizing property in Auto Layout. Try changing this property (for example, from Hug contents to Fixed and vice versa) or reload the tab.

Contents Tag Too Large and Why?

As I answered earlier, this label and arrows only appear when you interact with Figma’s UI, specifically with resizing properties that only auto layout frames have. With certain actions, these labels can stick, and will appear on all objects. To fix this, select any auto layout frame and hover over the horizontal or vertical resizing properties, or change the value of this property, or reload the tab.