Ctrl+J (togglePanel) doesn't close panel when maximized and center-aligned

[flavionn]

Does this issue occur when all extensions are disabled?: Yes

• VS Code Version: Insiders (latest)
• OS Version: Manjaro XFCE (Linux)

Steps to Reproduce:

1. Set panel alignment to "Center" (right-click panel → Align Panel → Center)
2. Maximize the panel (Alt+; or command "Toggle Maximized Panel")
3. Try to close the panel with Ctrl+J or by clicking the close button (X)

Expected: Panel closes
Actual: Nothing happens. Neither Ctrl+J nor the close button work when panel is maximized.

Note: Related to #279932 but different issue - that was solved by changing alignment to Justify, but I need center alignment with maximize support.

[ThanhNguyxn]

I've analyzed this issue and identified the root cause.

Root Cause:
In src/vs/workbench/browser/layout.ts, the setPanelHidden() method calls toggleMaximizedPanel() after the panel visibility has already been changed (line 1969). When toggleMaximizedPanel() tries to unmaximize, it calls setEditorHidden(false), which has a guard at line 1798-1799 that forces the panel visible if the panel is hidden. This creates a conflict - the panel can't close because hiding it triggers showing it again.

Proposed Fix:
Move the toggleMaximizedPanel() call to execute before the panel visibility is changed, preventing the conflict.

I'd like to work on this issue if that's okay. Happy to submit a PR with the fix.