Steps:
Import a model with skeleton (i used default no toes)
Press the IK Rig + button

Press the IK Rig - button
it is removed
Press the IK Rig + button again

Press the IK Rig - button
it is removed
Press the IK Rig + button again

Thank you for your continuing work
Steps:

Import a model with skeleton (i used default no toes)
Press the IK Rig + button
Press the IK Rig - button
it is removed
Press the IK Rig + button again

Press the IK Rig - button
it is removed
Press the IK Rig + button again

Thank you for your continuing work