New features and improvements:

Bridging behavior over rectangular empty spaces and infill are now placed in a smarter way. The bridge lines are now anchored to layers below where possible. Bridge lines can now also be interlaced for improved quality.

Fewer mistakes, less wasted time. Settings for disabled extruders are now greyed out to prevent "ghost editing," where you might spend time fine-tuning the Printing Temperature or Retraction Distance for Extruder 2, only to realize later that the entire model was set to print with Extruder 1. Additionally, a warning appears in the Preview stage if your model is hidden because an extruder is unchecked.

• Updated combing behavior for thin parts so it doesn't ooze over the walls by updating the behavior for Inside Travel Avoid Distance
• Added a warning in the preview if the reason you are not seeing your model is that the extruder is unchecked
• Self-intersecting infills like Grid, Triangular, and Cubic are hidden for some printers in recommended mode because they introduce artifacts at high speeds. They are still available in Custom mode
• Added height of the layer in preview mode in mm in addition to the layer number, contributed by @HellAholic
• Added a pop-up to help with using the Select Face mode when rotating a model, resolves #21359, contributed by @HellAholic
• Improved the reliability and maintainability of the Cura UI and Post Processing plugin, contributed by @HellAholic
• Added a new button under the Help dropdown to quickly open the log files, contributed by @HellAholic
• Updated the Filament Change script of the Post Processing plugin to support multiline Gcode Before and Gcode After, contributed by @hobbe and @GregValiant
• Updated the Z-Hop on Travel Post Processing script to include an option for Support Interface Only, contributed by @GregValiant
• Updated the Post Processing plugin with a bigger text area in the UI to allow for easier editing of multiple lines of Gcode, contributed by @HellAholic
• Updated the Advanced Cooling Fan Control Post Processing plugin to add an Enable and Fan Jump Start setting, contributed by @GregValiant
• Updated the Display Info on LCD Post Processing plugin to reflect Filament Cost and allow for the adjustment of the Cura estimated time, contributed by @GregValiant
• Updated the Purge Lines and Unload Post Processing plugin so the CUSTOM addition in the Gcode doesn't trigger an error, contributed by @GregValiant

New Settings:

New Honeycomb and Octagon infill types ensure the toolpath never crosses its own path on the same layer, reducing the chance of the nozzle hitting the infill during printing. Infill Start/End Move settings move the infill starts away from the wall to prevent surface blobs from a nozzle traveling to start a new infill line.

• Introduced Infill Start/End Move Inwards Length settings that add an extra line at the beginning and the end of your infill to prime the infill and prevent blobs on the outside wall
• Introduced Infill Skin Support to consolidate and replace Extra Infill Lines to Support Skin, Skin Edge Support Layer, and Bridging Over Infill Settings.
• Introduced a Middle option to the Z Seam Positions, contributed by @GregValiant
• Introduced a Print Estimation Factor to the Printer Settings that allows you to adjust the predicted printing time when you notice it deviates consistently from reality, contributed by @HellAholic

Bug fixes:

• Improved responsiveness when working with printers that are connected over Digital Factory
• Improved Scarf Seam behavior when used on overhangs and the visualization of these seams in the preview for improved troubleshooting
• Added an option to abort sending a cloud print job if the loading bar gets stuck
• Updated the behavior for One At a Time print jobs to reduce the chance of collisions at the end of the printing process
• Extruder End Gcode is now added to the end of the print process before Machine End Gcode, resolves #18018
• Fixed an issue where a model was still displayed as unprintable after switching the assigned extruder
• Fixed an issue where unretracted travel moves could be generated over top surfaces when the Inside Travel Avoid Distance could not be applied. Such moves are now retracted instead
• Fixed an issue where paint strokes on rotated models would not be picked up correctly when slicing
• Fixed an issue where combing would add a lot of unnecessary travels due to a very small slit in layer outline
• Updated the behavior of the preview tab when dragging and dropping in a Gcode file
• Fixed an issue where enabling Z hop when retracted would apply the Z hop twice and move the nozzle to X0 Y0 at start of the print, resolves #21132
• Fixed an inconsistency in the Language and Theme Combobox in preferences
• Fixed an issue that would cause a crash if the model was reloaded inside the paint mode
• Fixed an issue where Top Surface Expansion was being applied inside the model without any Top Surface area
• Fixed an issue where the flow of a fractional layer was not adjusted as expected
• Fixed an issue where UV unwrapping sometimes failed on complex shapes, leading to incorrect color or material painting
• Fixed a crash that could occur when exporting and sending very large print jobs over the network or Digital Factory Cloud
• Improved the robustness of network printing to reduce crashes and error states when communication with printers fails
• Fixed an issue where the configured build volume temperature limits could be bypassed in certain cases
• Updated the Annealing or Drying Post Processing plugin so it now also works on UltiMaker 3D printers, contributed by @GregValiant

Printer definitions, profiles and materials:

We’ve overhauled our print settings for the UltiMaker High Speed S-series to ensure your parts aren't just high-quality, but also high-performance. These updates deliver higher-quality prints at faster speeds, whether for prototyping or production.

• Updated wall settings for the UltiMaker S6 and S8 to improve wall strength
• Updated infill, skin, and shell settings for the UltiMaker S6 and S8 to reduce printing time and improve printed part quality
• Introduced Visual Intent for ABS and PETG for the S8
• Updated Retraction settings to reduce oozing and stringing in the UltiMaker S6 and S8
• Introduced a generic ASA profile for the Factor 4
• Updated the Brim Gap settings for UltiMaker 2+ Connect, resolves #21258
• Introduced Elegoo Centauri Carbon, contributed by @darthmolen
• Introduced Toybox Alpha name to include Toybox Alpha Three, contributed by @lukbrew25
• Updated settings for Elegoo Neptune 2 and Flsun V400, to have better default top layers with the infill set to 100%, contributed by @Asterchades