Currently, the buffer name is normalized to the `cwd` option value.
This buffer name is then used as the filename, which is used as the file
path for the previewer. But if the `cwd` value is not the actual cwd,
the buffer path can no longer be found by the previewer (relative to the
true cwd).
This is fixed by adding a `path` value to the entry that's the full path
of the buffer. The previewer will then use this full path to find the
file to preview.
ccaeeb5af5