My character is reoriented to face the direction I was last facing when opening the inventory.
This happens every 4 to 30 seconds, apparently depending on the graphics load (related MC-145447)
It happens in single player and multiplayer.
Potentially related to the fix introduced for this bug: MC-144107
It happens at all resolutions and in windowed or fullscreen mode.
A manually caused crash report is attached for additional info.
Please check if that's still an issue for you in the latest 1.14.4 stable release or the latest 1.15 development snapshot.