Flip Animation has wrong keyframes at timestamp 0

[Cubouse]

What are you trying to do, and what do you expect to happen?

Using Flip Animation to create the other side of an animation with the option "offset by half the animation length".

What happens instead?

The wrong keyframes is generated at timestamp 0.

It should have the values at half the animation length on the original channel, but it seems to pick a keyframe to copy instead, and not the right one (the next one over on the initial channel).

The issue does not occur when there are only 3 keyframes or less to flip.

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In the animations of this video, I had the snapping value at 50, so there wasn't any issue with fitting the new keyframes at the proper timestamp, like in #2151. Only the values are wrong, for those at timestamp 0, but the issues seem somewhat related to me.

Copying the last keyframe in the new channel, and pasting it on timestamp 0 "fixes" the issue.

bb_bug_flip_anim_wrong_kf.mp4

Model format in which the issue occurs

All with animation tab

Blockbench variant

Program

Blockbench version

4.10.0 Beta 2

Operating System

W10

Installed Blockbench plugins

N/A