Workspace panel grouping is not preserved for new projects (Project and Effects panels)

Premiere Pro Version:
26.2.2 (Build 3)

Operating System:
Windows 11

Description:

I have been experiencing this issue for several years across multiple Premiere Pro versions.

I use a custom workspace with three monitors. The workspace is saved correctly and almost everything is restored exactly as expected.

However, whenever I create a new project, the Project panel and the Effects panel are automatically grouped together into a single tab group, even though I saved them as separate panels.

All other panels, positions, sizes and monitor assignments are restored correctly.

Steps to reproduce:

1. Create a custom workspace.
2. Separate the Project panel and the Effects panel into different panel groups.
3. Save the workspace.
4. Close Premiere Pro.
5. Launch Premiere Pro.
6. Create a brand new project.

Expected result:

The workspace should be restored exactly as it was saved, with the Project and Effects panels remaining separated.

Actual result:

Only these two panels are merged into a single tab group. All other workspace settings remain unchanged.

Additional observations:

• This issue only occurs when creating a new project.
• Existing projects preserve the panel layout correctly.
• The issue has persisted across multiple Premiere Pro versions.
• Three monitors are permanently connected and powered on.
• I already tested saving the workspace again and even making the workspace configuration file read-only. The behaviour did not change.

Because existing projects preserve the layout correctly, this appears to be related specifically to the initialization of new projects rather than the workspace itself.