Showing transparency went wrong everywhere

[Destroy666]

Initially transparency was correctly showing as nothing (just drawing whatever is behind it) everywhere - viewer, file list thumbnails, preview, fullscreen, etc. For all PNGs and also bunch of PSDs, but not all of them.

Then I tried the "Fix alpha channel" Formats -> Read setting. Enabling it caused all PNGs and PSDs to go into the same state that just some PSDs incorrectly had earlier - with the alpha showing as white/gray checkerboard instead.

Turning it back off didn't achieve anything. How to get old real transparency again everywhere?

XnViewMP 1.8.2 x64 on Windows 10.

[xnview]

could you post sample file and screenshot?

[Destroy666]

Here's an example of thumbnails showing correctly and incorrectly:

Two with white background are incorrect.

Then the previews and fullscreen of the correctly shown thumbnails have the checkerboard:

I would like to show the transparency as indeed transparency, not checkerboard.

This is the image as .png, can't upload .psd which is also incorrect:

[XnTriq]

Please try deactivating Use checkerboard background pattern as background in Tools → Settings… → View.

[Destroy666]

Thanks, that fixed the problems in preview/fullscreen, Not sure what activated the option in the 1st place as I had it disabled eartlier.

Thumbnails are still random in terms of backgrounds though. Is it possible that multiple geneation methods are used? I use Icaros for those normallyy.

[XnTriq]

Thumbnails are still random in terms of backgrounds though. Is it possible that multiple geneation methods are used?

This has been changes recently.
Could you please select the files in XnView's browser and then got to View → Rebuild thumbnails?

[Destroy666]

That (temporarily) fixes it but not for all files.

E.g. this PSD stays with white background: https://www.sendspace.com/file/9fral8

[XnTriq]

Thanks for the sample!
You have to deactivate Use embedded thumbnail in Tools → Settings → Thumbnail.

[Destroy666]

That did it, thanks. So the only problem left is that the thumbnails go back to the white background randomly. Rebuilding then brings them back to how the should be.