Types of execution - System Mode or User Mode?

Overview

I was trying to prepare a consolidated list of different types of executions and if those are executed in System mode or User mode.

Taken from my popular question: Types of execution

What it actually means?

User Mode - Profile level permissions, field-level security, and sharing rules of the current user are enforced.

System Mode - Object permissions, field-level security, sharing rules aren't applied for the current user.

Comprehensive list

• Trigger - System
• Validation Rule - System
• Auto Response Rule - System
• Assignment Rule - System
• Workflow Rule - System
• Escalation Rule - System
• All Types of calculation behind formula, Rollup Summary - System
• Process Builder - System
• Visual Workflow or flow - User
  • if flow is called from Process Builder - System
  • if flow is called from Workflow - System
  • if flow is called from Apex - (depends on with or w/o sharing of apex class)
  • if flow is called from Custom Button - System
  • if flow is embed in Visualforce - Depends on VFP context
  • if flow is called from REST API - System
• Approval Process - System
• Publisher Action - System
• InvocableMethod
  • if this is called from flow - User
  • if this is called from Process Builder (does it depends on with or without sharing is specified on that Class) - System
  • if this is called from REST API - (depends on with or w/o sharing of the class)
• Custom Button - System
• Test method with System.runAs() - User
• Test method without System.runAs() - System
• Visualforce Page (StandardController) - User
• Visualforce Page (StandardController with extension) - System
• Visualforce Page (Custom Controller)
  • depends on with or without sharing of the controller
• Visualforce Component - depends on Visualforce page where it is used
• Macros - System
• Annonymous Apex - User
• Chatter in Apex - User
• Email Service - User
• All types of Jobs - System
• Apex Webservices (SOAP API and REST API) - System (Consequently, the current user's credentials are not used, and any user who has access to these methods can use their full power, regardless of permissions, field-level security, or sharing rules.)