- New Hungarian, Norwegian Nynorsk, Thai, and Ukrainian translations, thanks to the help of several contributors
- Improved performance in "Recover Files" tab #4610
- New "Reset" page in Edit > Preferences #4432
- New "Reset Symmetry to View Center" option t/19185 #4638 (thanks to @S4HRKBOY)
- New criterias to match similar RGB colors with color palette entries t/9682 #2787
- Added "Don't show this alert again" when saving WebP files #4658
- Fixed "Merge Down" command when the merged cels have a special z-index t/22106 #4468
- Fixed bug where we weren't able to uninstall third party extensions #4622
- Fixed transparent color bugs converting between RGB <-> Indexed conversion #4370 #4438
- Fixed moving multiple tilemap layers at the same time #3144
- Fixed right click action with shading ink is selected #4520
- Fixed bug where the first mouse click after a Ctrl+Z was ignored if we had Ctrl key configured to drag the "Brush Size" t/22112 #4484
- Fixed duplicate items in keyboard shortcuts list #4387
- CLI: Fixed exporting Sprite Sheet with group names #4456
- Lua API:
- New app.fgTile/bgTile properties to get/set the foreground/background tile #4403
- Added Site.tilemapMode property
- Added x and y params to app.command.Paste()
- Fixed app.command.Cut/Paste in -batch mode #4354
- Fixed app.command.Cancel() command when used from scripts
- Fixed default color/bgColor params in app.useTool()
More information: https://community.aseprite.org/t/aseprite-v1-3-9/23578/1
