No, it's not possible to keyframe any particle parameters. It wouldn't help much anyway since the random seed the particle layer uses prevents it to loop. What people do instead is rendering the particle effect, re-import the video file, duplicate it, and do a fade between them. The result will be ...

I recently made a gif using particle layer but i want it to loop So the first keyframe must be the same on the last keyframe Is there any method or script to keyframe particle I tried to turn on the particle on the timeline it’s the only thing to keyframed and copying it and pasted on the timeline d...