Hello.
Found the following: for this employee
https://zavod.crm-onebox.com/admin/shop/users/44/ it is enough to go to any bp "001 Checkout" (like the bp in the example in the first post), as the responsible field jumps to "Nobody". In this case, the change will not be saved until the employee clicks "Save" (hence the simultaneous introduction of changes in the history, as if the action or procedure worked out). Such behavior is observed at any stage of this (and only this) bp, regardless of the fact that at the stage or in the procedures there are no actions to change the responsible.
Summarizing: the employee changes (but does not save) the field data simply by going to the bp, which should not be.
Please help me find the reason for this behaviour. Tried to go to other bp under this employee - everything is fine. tried to enter the problematic bp under other employees - everything is fine too.