Tabs: adding/removing tab work not properly

[eaa]

Describe the bug
Adding tab before selected one makes mess between TabList and TabPanels

PS: Removing tab before selected also work not properly

To Reproduce
https://svelte.dev/repl/8c41f9b5b65248a9b52b2fbe7caba11d?version=4.2.9

1. Navigate to "Tab 3"
2. Check checkbox "showTab2"
3. Observe content of "Tab 2" and "Tab 3"

Library version
2.0.0