When the player has the slow falling effect and engages the elytra, and then proceeds to rapidly move the cursor in one direction to make the player spin, it prevents any forward movement and even in some instances makes the player descend even slower, rather than just continuing to move forward. While this is happening the player and elytra model may glitch and disappear and reappear while in this state. It is possible to return to normal by shifting the cursor enough upwards or downwards, and then the player with the engaged elytra will proceed to move normally again. There was nothing unusual in my game's logs after performing the glitch several times.

In the attached video I do it twice, with the first demonstration's descending speed barely even noticeable, while with the second demonstration the player descends at the normal slow falling rate, but exhibits the glitch with the player model. In both instances the player cannot move forward, only downwards until the cursor is moved enough.