ROX doesn't check permissions to read a file
before opening it as VFS. It leads to VFS fail,
as VFS has no right to read file contents.
Try it with
chmod -r at any archive file VFS supports
now "Open as AVFS" from menu
You'll get an error message from AVFS, but it is too
general to be useful.
ROX has to check necessary rights before calling AVFS
And please check it for "Run command" too.
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