Thumbnail becomes noise

[Troken]

To whom it may concern (guess who).

Sometimes in 1.92.1 thumbnails from totally normal images become very noisy (= understatement – plz view the image below). A bug?

I have to add that the image was made and saved in XnView itself, no external software used. And I have tried to "rebuild thumbnail", but no effect.

[xnview]

To whom it may concern (guess who).

Sometimes in 1.92.1 thumbnails from totally normal images become very noisy (= understatement – plz view the image below). A bug?

I have to add that the image was made and saved in XnView itself, no external software used. And I have tried to "rebuild thumbnail", but no effect.

???? If you rebuild thumbnails you have the same? It's a jpeg file?

[Troken]

???? If you rebuild thumbnails you have the same?

Yes, it does not help.

It's a jpeg file?

Yes.

The problem have happened a couple of times, I am not sure it only happens to JPGs, next time I will pay attention.

[Troken]

Don't know if it is related, but I have some TIFs in CMYK that also have strange thumbs, preview and fullscreen. It gets inverted. In Photoshop, the image has normal color.

EDIT: "Rebuild thumbnail" does not help.