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

• VS Code Version: latest main
• OS Version: Pop!_OS 24.04

Steps to Reproduce:

1. Try to open a folder while running under COSMIC
2. Observe that the GTK fallback shows up rather than the COSMIC native option

vscode requires version 4 of the FileChooser portal, which only launched a stable version in xdg-portal-desktop a few months ago. COSMIC actually fully supports version 4, but because xdg-portal-desktop advertising version 4 is still very new, everyone using this environment has the fallback GTK dialog.

vscode requires version 4 due to current_folder support, which COSMIC has:
https://github.com/pop-os/xdg-desktop-portal-cosmic/blob/master/src/file_chooser.rs#L32 (defining)
https://github.com/pop-os/xdg-desktop-portal-cosmic/blob/master/src/file_chooser.rs#L392 (consuming)