File browser has different sorting of files than viewer, how to fix it?

[postcd]

Sometimes I need to change sorting of files in XNView MP (1.8.6 Linux .deb) file browser yet I prefer image viewer (when i doubleclick image to view in a full screen) to display always alphabetically. I continuously forget to switch back to alphabetical.

I think that I have been told it is not possible to separate browser and viewer sorting, which is bad.

So I have set alphabetical sorting in browser, yet when i double-click image to open viewer and hit arrows left/right, it displays different images than the browser.

Browser under green arrows icon (sorting) has sorting by "Name", "Ascending", "Name - Alphabetic order". I have tried also other combinations of alphabetic orders but without the luck.

When I go to settings, search for "sort", there is "File list" page, where is ticked only "Folder always sorted alphabetically" in Sorting section. I have also tried various combinations here.

File names does not seem to contain any special characters.

UPDATE: I have just noticed that the image files are missing extension.

Similar without solution: How to change "Sort By" quickly while in image viewer?

[postcd]

Despite file has no extension, it is displayed correctly by Xnview, XNview should also browse such extension-less files properly sorted. It is not the case. Here you can try to reproduce on these files.

[xnview]

In Viewer which order do you have?

[postcd]

In Viewer which order do you have?

Viewer? I read that the browsing happens based on which column header I click in Browser (File -> Browser). My order there alphabetical A->Z.
1) File -> Browser
2) View -> Sort by -> Name, Ascending, Name - alphabetic order
I have been criticizing how Xnview is browsing files: viewtopic.php?t=46199