Well, for the time being, I would like to keep it as it is. In fact, I realised that changing the look of the tooltip itself would not help. One would need to change the area where a tooltip is to be expected, e.g. by a different background colour or something eye-catchy; this should be consistently used throughout the game, though, I guess, else it would not be nice. Further suggestions are very welcome. AFAIK it, I can later further edit this patch in this regard, i.e. also after it has been implemented, right? Or should I then better start a new one - to have the implemeted one as basis for a new diff?