Thanks! That solved my first problem. I didn’t add my object names into each clip like you did:
new THREE.VectorKeyframeTrack('redCube.position' ...
By doing that the animations are saved together with each object. However it created a new problem, since the exported gltf now has 2 animations that does not necessary start at the same time. What I need is this to be exported “as one” animation. I started a new question about this: