https://github.com/mrdoob/three.js/wiki/Migration-Guide#r125--r126 https://github.com/mrdoob/three.js/milestone/39?closed=1

Source

• Global
  • More usage of ES6 classes. #21206, #19985, #21229, #21235, #21232, #21231, #21266, #21285, #21293, #20013, #20100, #20102, #20014, #20009, #21319, #21327, #21342, e7ba1550cd07204d64d86e8913a8103a0c8fb516, 5df56b849f7433d3d6fedbcddb5599a2b38ce47c, 6100437b3e4d83c176e8ec82bf764e71df32f308, 330b18605ae145604f4168cf70802621f11ea2a1, 81487f294d8f69966f575716aae632f1ad9584ac, e9e9bcda18d9f85f5d3ce932e4cffb66f717cad6 (@mrdoob, @Mugen87, @DefinitelyMaybe, @linbingquan, @ianpurvis)
  • Remove TypeScript type declaration files. #21174, #21197 (@mrdoob, @Mugen87)
  • Remove obsolete code in Three.Legacy.js. #21181, #21219, #21310 (@Mugen87, @mrdoob)
  • Added "sideEffects": false in package.json. #21313 (@mrdoob)
  • Removed polyfills.js. #21314, 0c815022849389cbe6de14a93e1c2fc7e4b21c18 (@mrdoob)
  • Stop IE support. #21344, b4b24e310cbb825b8caf1eb7536513c4c33d21b9, d401181625d49b86cc910ed1fec8745c07b97579, 676115e5c72f66182a423eda5befd4922d5f9359 (@mrdoob, @Mugen87)
• CubeCamera
  • Simplify update(). #21331 (@linbingquan)
• Face3
  • Remove from core. #21164, #21161, #21394 (@Mugen87, @elisee)
• ImageBitmapLoader
  • Add support for request headers. #21283 (@gkjohnson)
• Material
  • Honor lightMapIntensity in .toJSON(). #21166 (@Mugen87)
  • Move flatShading to supported materials. #21200 (@Mugen87)
• Matrix3
  • Remove superfluous copy in .getNormalMatrix(). #21311 (@Mugen87)
• Mesh
  • Check Matrial.skinning before applying bone transform in raycast(). #20830 (@zach-capalbo)
• Object3D
  • Fix world matrix update bug in .attach(). #20759 (@takahirox)
• Quaternion
  • Add early out in slerpFlat(). #21183 (@jure)
• Raycaster
  • Simplify code. #21280 (@Mugen87)
• SkinnedMesh
  • Remove legacy warning. #21193 (@Mugen87)
• UniformUtils
  • Honor quaternions in cloneUniforms(). #21268 (@jure)
• WebGLCubeRenderTarget
  • Add missing texture configuration. #21309 (@Mugen87)
• WebGLRenderer
  • Add workaround for Adreno GPUs gl_FrontFacing bug. #21205, #21307 (@mrdoob)
  • Fix extension warnings. #21204 (@Mugen87)
  • Add possibility to bind 3D textures and 2D textures array as color attachment to framebuffer. #20111, #21243, dfaed955ea446793cdd93641cb8bed65f6575608, 341aa569e4eed79ee34be34e27e35b941a0a7983, effe04bb474904aa136fa5e79c75eca1a29782ac (@DavidPeicho, @mrdoob)
  • Add .copyTextureToTexture3D(). #21244 (@DavidPeicho)
  • Replace perturbNormal() implementation with a more robust version. #21299 (@zeux)
  • Stop default color space conversion. #21336 (@takahirox)
• WebGLRenderLists
  • Use stack approach. #21254, af07e8ad159a7106da5d2984813e3a282a8e4b75 (@Mugen87, @mrdoob)
• WebGLState
  • Implement true reset. #21281, #21295 (@Mugen87)

Documentation

• Improved Chinese translation. #21163, #21215, #21226 (@1993heqiang, @arthur7921, @buglas)
• Improved Creating a scene page. #21216 (@bukzor)
• Improved GLTFLoader and GLTFExporter pages. #21261, #21262, #21275, #21277 (@takahirox, @eltociear)
• Improved Installation page. #21258 (@Mugen87)
• Improved SpriteMaterial page. #21176 (@Cloud9c)
• Improved WebGLRenderTarget page. #21306, #21308 (@gsimone, @Mugen87)
• Improved Useful links page. #21218 (@leonsbuddydave)
• Fix broken example links. #21180 (@Mugen87)
• Fix broken link to ImageBitmap MDN documentation. #21291 (@gonnavis)

Examples

• Clean up. #21184, #21191, #21296, #21335, #21349, 39601236e150caf0dc73e3acf1c89821f51a7c2e (@Mugen87, @schmijos, @mrdoob)
• Regenerate RGBM textures. #21173 (@Mugen87)
• Fix toJSON() methods for certain node material classes. #21211 (@Mugen87)
• Added misc_exporter_usdz example. #21251 (@mrdoob)
• Simplify webgl_instancing_scatter example. #21250 (@Mugen87)
• Removed some not so useful examples. #21252, 2dbcb41d02ef3e7457dab2b3353d5c73f11ba793 (@mrdoob)
• Fix copyright link in webgl_loader_gltf_variants example. #21276 (@takahirox)
• Make mirror examples resizable. #21297, 1880f08b992a302956021bfb1d08fdc689285924 (@gonnavis, @mrdoob)
• Remove superfluous texture settings in (S)SAO pass. #21329 (@gonnavis)
• Updated fflate to 0.6.2 and removed fflate-deflate. 388d9090ce05b0c022bae74c60c4ce42943c500e (@mrdoob)
• Add SSRPass and webgl_postprocessing_ssr example. #20156 (@gonnavis)
• Add webxr_ar_lighting example. #20876, c63bdaf8cabb347c3ab7188924890a7452453d75 (@toji, @mrdoob)

• 3DMLoader

  • Adding updates. #21248, #21347 (@fraguada)

• AnaglyphEffect

  • Use Dubois matrices. #21302 (@Mugen87)

• BufferGeometryUtils

  • Fix assignment bug in .computeMorphedAttributes(). #21303 (@Mugen87)

• CSS2DRenderer/CSS3DRenderer

  • Removed IE support. #21317 (@Mugen87)
  • Remove old css prefixes. #21321 (@yomotsu)

• GLTFExporter

  • Add plugin system for extensibility. #20842 (@takahirox)
  • Fixed supported material check. 9ea6a221c4ec99ec9a2d932e881cbbf6c8282ba9 (@mrdoob)
  • Fixed accessor reference. 9d8ed2778efdc6d71221865d03dec7d83d281ff3 (@mrdoob)

• GLTFLoader

  • Make error when loading textures with no data clear. #21177 (@zeux)
  • Revert usage of .computeTangents(). #21186 (@Mugen87)
  • Add before/afterRoot hook points. #21207 (@takahirox)
  • Remove support for MSFT_texture_dds. #21271 (@donmccurdy)
  • Fix bug when loading external WebP texture #21282 (@gkjohnson)

• NRRDLoader

  • Improved gzip detection code. #21213 (@IsseiMori)

• SVGLoader

  • New parseFloats() implementation. #21195 (@Mugen87)

• USDZExporter

  • Added textures support. #21245, #21247, b3974180cde63d86ebab3faed839dfe3ae422df0 (@mrdoob)
  • Reduce vector precision. e35432aab63846ff6269a818fb3666dd6b4d3957 (@mrdoob)
  • Added uv2 warning. 4ad0d3c476d358207b9b319279fd4622a673b970 (@mrdoob)
  • Removed unnecessary lines. d92ea73c3cba8aa756ee7295946e00f86b3bdf7c (@mrdoob)
  • Improved resizing code. 1e210ac8f57d43dd2039b962394c181ef5c25bdc (@mrdoob)
  • Implemented 64byte alignment. 8000053e53fa3167d0d7d836808c54fd0f5f6975 (@mrdoob)
  • Define emissiveColor only when required. ec7718144d9b4e8fd7f912627cd00550faba983b (@mrdoob)
  • Clean up. ff0e2e1b1b3b97358f71a271070039a896abdab1 (@mrdoob)
  • Resize textures to 1024 by default. aa5bb104d2e74a007d19e2f08dcec3a05b134004 (@mrdoob)
  • Improved material parameter nodes. d5326ca5048ec0f37b40f4db833197d172770756 (@mrdoob)
  • Fixed exporting Xforms with duplicated names. ac377cf530fbd03d1bf50bc84aa839801d803919 (@mrdoob)
  • Added material.emissive support. d1de1f019723c58e5eadc14ebec4adcfc554bf05 (@mrdoob)
  • Fixed normals. ddc530d9d0602094ba6af7fb0df9f7bdb246f099 (@mrdoob)

• VOXLoader

  • Fixed chunk parsing. a36141f54a4cdf278ac1ddd29a14bc17e7a28b4b (@mrdoob)
  • Added VOXDataTexture3D. c460b28646ee6b1ecd6efa6bcb5d6d26976d4114 (@mrdoob)
  • Clean up VOXMesh. 9fa202c2354e6621855d4f6d44e19674ab533aa9 (@mrdoob)

• VRMLLoader

  • Apply DEF-name to node names. #21217 (@Mugen87)

• WebGPURenderer

  • Fix uniform updateVector4(). #21160 (@sunag)
  • All UBOs and varyings are generated by node material now. #21170 (@sunag)
  • Update to latest WebGPU API. #21194, #21345 (@Mugen87)
  • More node classes and bug fixes. #21208 (@sunag)
  • Rename ModelViewProjectionMatrixNode to ModelViewProjectionNode. #21253 (@sunag)
  • Set material dispose listener only once. #21346 (@Mugen87)
  • Fix material compile per object and new instance uniform example. #21350 (@sunag)

Editor

• Clean up. #21325 (@1993heqiang)
• Call .dispose() on textures. #21159 (@Mugen87)
• Refactor UI classes. 794af189a146acdbc23507f10bec6d65112e8224, 76ac160f07f80ef3500e1b8e2db4f4eb84122272, 2f30e75cc9055af3c91f3f14acc1691902565c5f, c513508c179d258a0be03552991beee24f82cdf2, a501950082d00f063507e0913ae623408981a2e1, 4885b4c2238d832430495464cdb999262ad0ab77, e5139eb6d699c7e17dab669771007eb971d6a0a4, 6b3b9d608077ec58430c38dcd24885744e91c1a7 (@mrdoob)
• Allow negative light intensity. f1fb6ee23b3784bca85acd82c232efdf0148c149 (@mrdoob)
• Added ffmpeg.wasm video renderer. #21221 (@mrdoob)
• Add center option. #21340 (@Mugen87)
• Rescued VR mode. #21351, 292e51c58f47eadd3c20329e0bee64bcb5009fa7, 292e51c58f47eadd3c20329e0bee64bcb5009fa7 (@mrdoob)

Tests

• Add BufferAttribute.toJSON() unit test. #21225 (@takahirox)