A new 'smoothing' option was added to write smoothgroups (the 'bitflag' version of it), in addition to normals and sharp edges or faces. Also see the original PR and underlying Blender API changes for more details.
Import: New experimental FBX importer (written in C++, based on ufbx). (PR#132406, PR#138367)
The Python based importer is still there; the new one is marked as "(experimental)" in the menu item. Drag-and-drop uses
the Python importer; the new one is only in the menu item.
New importer is generally 3x-15x faster than the old one, and often uses less memory too.
ASCII FBX files are supported now.
Binary FBX files older than 7.1 (SDK 2012) version are supported now.
Better handling of "geometric transform" (common in 3dsmax), manifesting
as wrong rotation for some objects when in a hierarchy.
Some FBX files that the old importer was failing to read are supported now.
Materials import more shader parameters (IOR, diffuse roughness,
anisotropy, subsurface, transmission, coat, sheen, thin film) and shader
models (e.g. OpenPBR or glTF2 materials from 3dsmax imports much better).
Importer now creates layered/slotted animation actions. Each "take" inside
FBX file creates one action, and animated object within it gets a slot.
Materials that use the same texture several times no longer create
duplicate images; the same image is used.
Material diffuse color animations were imported, but they only animated
the viewport color. Now they also animate the nodetree base color too.
"Ignore Leaf Bones" option no longer ignores leaf bones that are actually
skinned to some parts of the mesh.
Import settings that existed in Python importer, but are not done in the new
one (mostly because not sure if they are useful, and no one asked for them
from feedback yet):
Manual Orientation & Forward/Up Axis: not sure if actually useful. FBX
file itself specifies the axes fairly clearly. USD/glTF/Alembic also do
not have settings to override them.
Use Pre/Post Rotation (defaults on): feels like it should just always be
on; ufbx handles that internally.
Apply Transform (defaults off, warning icon): not sure if needed at all.
Decal Offset: Cycles specific. None of other importers have it.
Automatic Bone Orientation (defaults off): feels like current behavior
(either on or off) often produces "nonsensical bones" where bone direction
does not go towards the children with either setting. There are discussions
within I/O and Animation modules about different ways of bone
visualizations and/or different bone length axes, that would solve this
in general.
Force Connect Children (defaults off): not sure when that would be useful.
Often turns animated armatures into garbage when used.
Primary/Secondary Bone Axis: again not sure when would be useful.
Python API of the old importer was bpy.ops.import_scene.fbx; API of the new one is bpy.ops.wm.fbx_import.
The plan is to remove the Python importer add-on at some point in the future.
Add support for writing ProRes codec videos (7d75c5e2bc)
OpenEXR:
Read and write ACES2065-1 colorspace metadata, to auto detect this colorspace in Blender and other applications. (PR#135823)
Preserve compression and bit depth settings when re-saving files. (PR#135656)
Color Management: Support OpenColorIO file rules to auto detect color space. The Blender configuration does not contain such rules, but other configurations set through the OCIO environment variable can. (PR#136516)