https://bugs.kde.org/show_bug.cgi?id=520521
--- Comment #1 from xynrin <[email protected]> --- (In reply to xynrin from comment #0) > Created attachment 192540 [details] > icon is ? > > ### Description > After upgrading to Fedora 44 (KDE Plasma 6.6.5, Wayland session), icons for > several third-party applications (e.g., CLion, PyCharm, Omniget, Cockpit > Tools) in the Task Manager/System Tray appear as generic gray document icons > with question marks (or completely blank on some themes). > > The root cause was tracked down to the icon lookup engine failing to resolve > fallback icons. Third-party apps place their icons in > `/usr/share/icons/hicolor/`. In `hicolor/index.theme`, `Hidden=true` is set > by default. It appears that the Qt6 icon loader or KDE's `KIconLoader` > completely skips scanning the `hicolor` directory when initializing or > processing the theme inheritance chain if `Hidden=true` is present, causing > a broken inheritance chain and returning `null` to the QML rendering > delegates. > > ### Environment > - OS: Fedora Linux 44 > - DE: KDE Plasma 6.6.5 (Wayland session) > - WM: KWin > - Graphics: NVIDIA GeForce RTX 5060 Mobile (Using proprietary drivers) > - Icon Themes tested: Papirus-Dark, Breeze, Breeze-Light > > ### Steps to Reproduce > 1. Install a third-party application whose icon only exists in > `/usr/share/icons/hicolor/...` (and not pre-baked into themes like Breeze or > Papirus). > 2. Pin the application to the Task Manager or launch it under a Wayland > session. > 3. Observe that the icon displays as a gray question mark. > 4. Check `journalctl --user`, notice repeating QML errors: > `ToolTipDelegate.qml: TypeError: Cannot read property 'containsMouse' of > null` when hovering over the broken icon. > 5. Running `kiconfinder6 <icon-name>` returns not found, despite the > `.png/.svg` file existing inside the `hicolor` subdirectories. > > ### Underlying Root Cause > Using `kiconfinder6` to trace the lookup chain reveals that themes failing > to explicitly declare inheritance properly, or even standard themes trying > to fall back to the system default, get choked off at the `hicolor` level. > > According to XDG Icon Theme Specifications, `Hidden=true` means the theme > should not be selected in the GUI configuration, but it MUST still be used > as a fallback lookup. Currently, Plasma 6 treats `Hidden=true` as "Do not > load this theme structure into memory hash/cache at all," causing a total > regression of the XDG fallback mechanism. > > ### Workaround > The issue can be verified and temporarily resolved by physically copying the > missing icons from the `hicolor` tree directly into the active icon theme > directory (e.g., `~/.local/share/icons/Papirus-Dark/`), forcing the lookup > loader to hit the icons at stage 1 before falling back to `hicolor`. -- You are receiving this mail because: You are watching all bug changes.
