Setting the 'Show Hidden Files Last' checkbox to 'Enabled' causes all (many?) View Settings to reset to defaults upon browsing to another folder or closing the Dolphin Instance. Settings that are reset include, but are likely not limited to: Show Hidden Files Show Hidden Files Last View Mode: Details, Compact, Icons Show in Groups
Issue does not apply on Arch. KDE 6.5.4. To test: open dolphin click top right three lines hover on more hover on view change the three tickboxes there: previews groups hidden files hover on sort by hidden files last