You need to make a new "zero clearance" insert, that yellow thing has too wide of a slot in it, an accident waiting to happen.
Cut a piece of wood and plane it to the right thickness, trace and drill the screw holes, install it and make a cut in it. Now you have a zero clearance insert and nothing will get caught between it and the blade.
If you can't do that then cut a piece of plywood big enough to cover the whole saw base and stick it down with some double sided tape.
Miter saws have a lot of power so do everything you can to avoid kickback.