Allow admin submenu accessible when theme details model open

[jigneshnakrani088]

Trac ticket: https://core.trac.wordpress.org/ticket/62911

Problem:

The left admin submenu is unresponsive and cannot be accessed while the Theme Details modal is active.

Expected Behavior:

The left admin submenu should remain accessible and functional even when the Theme Details modal is open.

Solution:

• set z-index for #adminmenuwrap in between 10000 (.theme-overlay) to 99999 (#wpadminbar), which puts admin submenu above theme model and below the admin toolbar.

Before:

After

---

This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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Props jigneshnakrani.

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[github-actions]

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