KDE's Open/Save dialogs are widely considered to be the best in the Linux world, but there's far more we can do to make them truly exceptional. Here are some ideas.

Design goal 1: Optimize view modes for common use cases

We identify two common use search modes for locating files or directories: 1) based on their filenames or metadata, and 2) based on their content or appearance. For the former, a compact optimized list-style view with columns of additional information is ideal. For the latter, a large-icons-style view with previews is ideal. Implementing this will require the following changes:

• Always perfectly size and align column widths so that Detailed View and Detailed Tree View are actually usable: D11993
• Improve grid spacing so that Short View with "Icons on Top" is actually usable at medium and large sizes: D12306
• Show buttons on the toolbar to allow easily toggling between Short View and Detailed Tree View: D12077
• Fix previews to apply to all supported file types (fixes https://bugs.kde.org/show_bug.cgi?id=318493): D12389
• Make Previews only show up for icons (in any view mode) larger then 24px or so, as they are unusable and useless at such small sizes: D12321
• Turn on previews by default: D12328
• Make the view modes match the ones in Dolphin (e.g. Icons, Compact, and Details, with an option for "Allow expansion" in the settings menu: D21315
• Make KDirOperator display Detailed Tree View by default: D12327
• Use recentlyused:/ ioslave in the places panel to display recently accessed files by this application: D7446

Design goal 2: improve efficiency and safety of overwrite behavior

(Relevant information: D12346#249638)

• Allow the file dialog to trigger overwrite on double click (irrespective of the click setting) without having to additionally click the Save button afterwards (fixes https://bugs.kde.org/show_bug.cgi?id=267749): D12538
• Make Kate delegate overwrite behavior to the dialog, rather than handling it itself D21401 D21402
• When clicking on a filename in the view, the text in the filename field gets replaced, so provide an easy way to undo that if you didn't mean to (fixes https://bugs.kde.org/show_bug.cgi?id=449038) - https://invent.kde.org/frameworks/kio/-/merge_requests/1807

Fix important bugs

• Always save view settings when canceling or closing the dialog: D12227 and D12240
• Fix/reduce the scroll speed when icons are very large (fixes https://bugs.kde.org/show_bug.cgi?id=223937; see also the same problem in Dolphin: https://bugs.kde.org/show_bug.cgi?id=386379): D25683
• Always save view settings when switching from one view mode to another (e.g. from Short View to Detailed Tree View and back. D21459
• Fix keyboard navigation with Icons-on-the-side in Short View (fixes https://bugs.kde.org/show_bug.cgi?id=148635)
• Disable the zoom buttons once the slider reached either end: D12590
• Set a minimal size for the zoom slider: D12588
• Fix a bug where after every save the places panel got 1px wider: D12592
• Perfectly align the name widget to the file view: D12594
• Fix the flickering when previews are turned on and icons are resized using the slider
• Fix location of progress bar that appears when the file list takes a long time to load (Fixes https://bugs.kde.org/show_bug.cgi?id=194017)
• Fix bug that prevented select-filename-on-click from working with double-click: D19849
• Save places panel width also after hiding panel: D12593
• ⇥ key only switches between location bar, file view, and text fields in a loop once the file view gains focus (Fixes https://bugs.kde.org/show_bug.cgi?id=466209) - https://invent.kde.org/frameworks/kio/-/merge_requests/1805
• Cannot open files that start with a tilde (fixes https://bugs.kde.org/show_bug.cgi?id=317513) - https://invent.kde.org/frameworks/kcoreaddons/-/merge_requests/489 - https://invent.kde.org/frameworks/kcoreaddons/-/merge_requests/489
• Cannot save a file named "file".txt (i.e. it includes double quotes) (fixes https://bugs.kde.org/show_bug.cgi?id=426728) - https://invent.kde.org/frameworks/kio/-/merge_requests/1834
• Fix issue with preview panel showing the wrong file when the cursor passes over another item and leaves the KDirOperator viewport without first passing over the background (fixes https://bugs.kde.org/show_bug.cgi?id=247268)
• Save dialog: focus unexpectedly shifts to the filename field after using arrow keys to navigate in the file view (Fixes https://bugs.kde.org/show_bug.cgi?id=466206) - https://invent.kde.org/frameworks/kio/-/merge_requests/1860
• Selection markers not shown when the click mode is Single Click (fixes https://bugs.kde.org/show_bug.cgi?id=185793) - https://invent.kde.org/frameworks/kio/-/merge_requests/1850
• When multi-selection is allowed, ignore any selected folders, and/or disallow folder selection when any files are already selected)(fixes https://bugs.kde.org/show_bug.cgi?id=271400) - https://invent.kde.org/frameworks/kio/-/merge_requests/1859
• Make sure items' sizing and spacing take into account font size, if changed from its default value

Generally improve polish and usability

• Make the dialogs open at a large size by default, and scale the default size properly when using high DPI mode (fixes https://bugs.kde.org/show_bug.cgi?id=411599): D25986
• When the dialog displays a combobox of file type options, display the string "File type:" instead of "Filter:" D20964
• Move the sorting functionality from the Settings button to a dropdown menu button on the toolbar to expose this otherwise-mostly-hidden functionality: D12337 (On file-dialog-improvements branch)
• Allow drag-and-drop to the KDirOperator part of the dialog, not just to the filename field: D20838 (only one file is supported, might want to expand the feature to multiple files drop when dialog is in multi selection mode)
• Make sure the return/enter keys are almost always bound to the Save or Open button (fixes https://bugs.kde.org/show_bug.cgi?id=385189)
• Improve thumbnail quality (fixes https://bugs.kde.org/show_bug.cgi?id=345578): D12385
• Don't include filename extension when auto-selecting the filename: D12544
• Re-word some menu items per T8552#140370 done in D20827
• When the view has focus, the ⇥ key should focus the filename field (Fixes https://bugs.kde.org/show_bug.cgi?id=409540) - https://invent.kde.org/frameworks/kio/-/merge_requests/1805
• Support for touchscreen scrolling in the file browser view (fixes https://bugs.kde.org/show_bug.cgi?id=406513) - https://invent.kde.org/frameworks/kio/-/merge_requests/1832
• Filter UI (Fixes https://bugs.kde.org/show_bug.cgi?id=179483) - https://invent.kde.org/frameworks/kio/-/merge_requests/1853
• When sorting by date, show newest first by default, not oldest (fixes https://bugs.kde.org/show_bug.cgi?id=500512) - https://invent.kde.org/frameworks/kio/-/merge_requests/1824
• Make toolbar span the full window width and use header styling, like Dolphin's does
• Synchronize toolbar contents with Dolphin's toolbar as much as possible
• Improve default width of embedded Places panel (fixes https://bugs.kde.org/show_bug.cgi?id=297217)
• Sort Supported File Types list alphabetically (fixes https://bugs.kde.org/show_bug.cgi?id=47750)

Implement important features

• Reload item in the context menu: D12215
• "Rename" item in the context menu (fixes https://bugs.kde.org/show_bug.cgi?id=189482) D17596 D17595 D17597
• Ability to jump to folders visible in Dolphin (fixes https://bugs.kde.org/show_bug.cgi?id=412668)
• Implement rubber band selection in list-style views (fixes https://bugs.kde.org/show_bug.cgi?id=271399)

Consider moonshot features

• Implement search (fixes https://bugs.kde.org/show_bug.cgi?id=164594)
• Add more sorting options (Fixes https://bugs.kde.org/show_bug.cgi?id=155583)
• Allow tagging files when saving them (Fixes https://bugs.kde.org/show_bug.cgi?id=412248)
• Implement Column view navigation: D7929