unfortunately I uploaded some pictures three times and they've been inserted into my album.
I didn't find a function for bulk delete within the gallery, so I decided to delete them on the webserver (they were clearly visible, because gallery named them *_001.jpg and *_002.jpg)
But now I'm still having the thumbnails in my album, it still counts 255 elements (although 70 got deleted).
I've tried to rebuild/resize all thumbnails - no luck.
How can I get rid of theses thumbs?
Do I have to delete them manually?