My recollection of kde 3.x is that all multimedia apps check the actual file for it's file type. That way the extension just needs to be a multimedia type and as these are some times incorrect also a sensible way to go. It's a sensible place to put the work as the file data is likely to contain info needed to display what ever it is. Preview also functioned on some missnamed files at least.
It also handled dots as Miroslaw requires. That in practice may have originally been down to software versioning where it's widely used. It's still functioning on my kde at least at the launch end. RPM's and compressed files can be sent where they are supposed to go. I would assume authors are saving without problem as well. :-) Can't help wondering is some are parsed from the tail and others from the head. On the other hand seriously launch seems to be ok and the problems seem to only relate to saving.
The only fix I could suggest is replacing dots with underscores (as I call them). Curiously these are seen in places which makes me wonder if some other systems have similar problems.
Of late I have seen another form of naming eg "photivo-794_a038f21c7828-148.3.x86_64.rpm". I have used the neg sign myself but found it caused problems when I used searches to collect together files before a subsequent machine change.
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