[BUG] Print layout broken: main content is not visible

[AdamFiser]

Describe the bug
When printing a page (or using browser print preview) in AdminLTE v4, only the sidebar navigation is visible. The main content area is either completely invisible.

To Reproduce
Steps to reproduce the behavior:

1. Open any AdminLTE v4 page (e.g. https://adminlte.io/themes/v4/docs/layout.html)
2. Open the browser print preview
3. Observe that only the sidebar is rendered — the main content area is "blank"

Expected behavior
The main content (cards, tables, widgets, text) should be visible when printing.

Screenshots
Screenshots are enclosed

Environment (please complete the following information):

• AdminLTE Version: v4 (RC4, master)
• Operating System: Windows
• Browser (Version): Chrome (latest), Brave (latest), Firefox (lastest), Brave (latest)

Additional context

• The sidebar renders correctly