The double-click fill/fit mode was hardcoded (image_canvas: _isFilled = true) and reset on every image change, so it never survived a restart. It is now stored as "filled" in window.json and restored on launch and on image switch. WindowPersistence.saveSync() now merges with the existing file, otherwise the startup/move/resize geometry writes would drop the mode key. Also: version 1.5.0, CHANGELOG entry, dist/ ships imajviewer_1.5.0_amd64.deb (replaces 1.4.2).