Hi !
I’m working in after effects 2021, my animation is very simple, trim path, gradient stroke, rounded cap at the end of the strokes.
After the export with Lottiefiles, the caps are squared. Sometimes it’s rounded. What is the rule ?
I need them rounded.
Please help 
The gradients strokes seem to be the problem. When I remove the gradients strokes and choose simple strokes (no gradient) the caps stay rounded after export.
I created an other project from scratch, path, gradient strokes, trim, rounded caps. And there is no problem.
There is no logic…
I removed the one color stroke, put a new gradient stroke… now the rouded cap stay rounded.
Problem solved but I do not understand how it appears and why it works now…
It could be 100% how you made the stroke initially and how you applied the gradient and the round caps. How your groups are made and how the stroke is generated.
I would compare the structure of both layers between both projects. If you want, you can share screen shots of those and we can diagnose that for future searches.
Rounded cap not supported for Lottie animation. Please see the supported parameters here Lottie Docs. Hope this help you
