Subsite - pages created on main site wrongly appearing on subsite

Silverstripe Version:

Have you experienced that similar issues with subsite?
In subsite - pages created on main site are appearing on subsite.

Somehow, pages which created in main site are wrongly appearing in subsite.
This is intermittently happened to me.

Although you have removed pages, those pages are back in subsite.
The pages are cloned with subsiteIDs.

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Hi @robbyahn

I know this exact thing is very possible when the CMS editor has multiple tabs open (with different sites in each). The sessions get confused and can cause this exact problem. It’s been outlined before here: Subsites not safe for multiple tabs · Issue #314 · silverstripe/silverstripe-subsites · GitHub

Perhaps that could be it?