tabs: tab "{id}" - badge must be true, a number, a string, or a function; got {type}. No badge is shown for this tab.

Warnings reference › tabs.badge.type:*

Identifier

tabs.badge.type:*

Raised by

Tabs

Since

1.59.0

What happened

The descriptor's badge was something the strip cannot draw. true means "show the live row count", a number or string is drawn as written, and a function is called with the count; anything else is refused rather than coerced, and the tab renders with no badge at all.

The fix

Use one of the four forms. badge: true is the usual one, and gives the live count.

The smallest fix

tabs: [{ id: 'open', title: 'Open', badge: true }]

Reference

Covered in full at the API reference.