Fix: Fixed issue where existing tabs were duplicated when opening a folder from the outside of Files

[hishitetsu]

Resolved / Related Issues

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  Closes Bug: Opening Files from explorer.exe causes tabs to duplicate #15107

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[gumbarros]

The AppInstances.Count == 0 if makes sense, thank you very much for the fix btw. But why is the LastSessionTabList no longer stored?

[hishitetsu]

But why is the LastSessionTabList no longer stored?

It is no longer needed when #14795 has been merged.