This is a follow-up to Bug 361047. Currently, when a group is expanded, it is not visually clear which images belong to the group. The original idea of changing the background color of such a group does not play well with different themes, and it also does not help with multiple opened groups (then all expanded images will have the same background color). A different idea would be to reduce the opacity of opened grouped thumbnails to e. g. 50 percent but only(!) while the mouse is (!) over the *main* group thumbnail. This does not affect visibility of the thumbnails during normal usage, it indicates clearly what is grouped, each group can be visualized separately, and it does not interfere with color schemes. Also, it creates the possibility of correctly sorting grouped images in between non grouped ones when the group is opened. This is slightly different from the idea in comment 76 of the above bug report which requested the opacity reduction when *not* hovering over one of the group. But doing it like that would again create the issue that multiple expanded groups cannot be told apart which would be confusing. If reduced opacity is not an option or too slow to compute, enlarging the border of all expanded image thumbnails (significantly - like 3..5x as many pixels) only when hovering above the main thumbnail would also be an option.
I did some suggestions back in the day (Bug #392936), but they would interfere with color labels and different themes. Following this threat to see where it goes.
*** Bug 462245 has been marked as a duplicate of this bug. ***
Git commit 245614fb1920996726a0cd59e49e5b64829f1937 by Gilles Caulier. Committed on 10/12/2025 at 14:03. Pushed by cgilles into branch 'master'. Enhancement: Grouped Items Usability Improvements This update introduces significant usability improvements for grouped items in digiKam: - Visual Highlighting for Open Groups: Previously, only closed groups were visually distinguished by a decorative border around the thumbnail of the stack's representative image. Now, each item within an open group is also highlighted with a colored border, ensuring better visual consistency and making it easier to identify group members at a glance. - Tree-View in Image Properties: The Image Properties right sidebar tab now supports a tree-view display for grouped items. Users can expand or collapse group stacks on demand, providing a more intuitive and flexible workflow. For a visual demonstration of these features in action, check out the screencast of digiKam 8.9.0: https://i.imgur.com/9QZ8kZw.mp4 Related: bug 512555, bug 392936, bug 401205, bug 499108 FIXED-IN: 8.9.0 M +4 -3 NEWS M +28 -0 core/app/items/delegate/itemdelegate.cpp M +8 -0 core/libs/widgets/itemview/itemviewdelegate.cpp M +1 -0 core/libs/widgets/itemview/itemviewdelegate.h https://invent.kde.org/graphics/digikam/-/commit/245614fb1920996726a0cd59e49e5b64829f1937