4KWALL: alle weergawes en ouer weergawes

Fixed
- Fewer crashes. 4kWall no longer crashes when a window closes with the
pointer on its edge, when you leave a page while wallpapers or downloads are
still loading, or when the app quits in the middle of a download.
- Thumbnails load reliably. When the same thumbnail was asked for twice at
once, one of the two could fail to load.
- Favorites keep working while the auto changer runs. The favorites list no
longer fails with "database is locked", and a favorites database that can't
be read no longer closes the app.
- A clear message when server has trouble, instead of "Expecting value:
line 1 column 1".
- The auto changer stops once 4kWall is uninstalled. On Flatpak, removing
the app together with its data while it ran in the background left the
changer running and failing.

Downloads
────────────────┬────────────────────────────────
Platform │File
────────────────┼────────────────────────────────
Linux (AppImage)│4kWall-2026.11.3-x86_64.AppImage
────────────────┼────────────────────────────────
Windows │4kWall.exe
────────────────┴────────────────────────────────
Linux: chmod +x 4kWall-2026.11.3-x86_64.AppImage then run it. Requires
glibc 2.31+ (Ubuntu 20.04+, Debian 11+, Fedora 34+, Mint 20+). No installation
needed. On systems without FUSE, run with --appimage-extract-and-run.
Windows: download and run 4kWall.exe.
Also on Flathub
and the Snap Store.