Portal access to local files.

[Simon McVittie]

On Tue, 15 Jun 2021 at 14:46:42 +0200, Alec Leamas wrote:
> Hm... let me try a little more here. After all, feeding the sandboxed
> xdg-open with a local HTML file in the from the main application in the
> sandbox works just fine.  Our problems seems to about plugins, which are
> dl-loaded flatpak extensions. It's the data here which doesn't seem to
> to be visible to xdg-open. I'll dig a little more when there is time.

My guess would be that the filesystem-handling code in
xdg-desktop-portal (approximately the same place I changed recently in
https://github.com/flatpak/xdg-desktop-portal/pull/590) doesn't know
how to remap paths that belong to extensions, only the main app and runtime.

    smcv