617 - 'Use only one viewer instance' not working ?

[etc.]

I'm not sure how this option will work, but even though I select this option, several internal viewers will open.

How to reproduce:
1. Go to 'Tools -> Settings -> Viewer' and check ON "Use only one viewer instance" option.
2. Click 'OK'.
3. Select an item on active list, and select 'File -> View'.
(An internal viewer will open.)
3. Again, select an another item on active list, and select 'File -> View'.
(An another internal viewer will open.)

Ok, there is a workaround. If I select 'File -> Link to file list' on internal viewer, no more open another viewers. But this option will not be saved.
Thus, I need to select it each time.

[Marek]

Fixed for the release 619.