Hector SLAM - Yawing issue + IMU Yaw fusion?

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I am using hector slam with an RpLidar (only 5-10 hertz). It works phenomenally well in a straight line, but when I yaw just a little aggressively, hector slam gets confused and doesn't detect a yaw at all. I assume it is due to scan distortions.

(I would upload an image if i could)

My question is if it is possible to manually input a true yaw value when the change in yaw is greater than a certain value?