When the conflict is with your supervisor, there is a power differential that can significantly impact the dynamics of conflict resolution.
You may not feel safe bringing it forward due to fear of retaliation or you may feel intimidated to speak freely with your supervisor. Building a positive relationship with them can help mitigate the impact of power differentials.
Follow the same best practices outlined in the conflict with a colleague section. As you reflect on the issues and approach the conversation, do not assume that they are intentionally behaving in a particular way. They may not be aware of how their behaviour/actions are perceived by you and others.
If, from your perspective, the issue(s) cannot be resolved through an informal and open discussion or you do not feel comfortable engaging in a conversation, it is recommended that you contact Human Resources (staff) or Academic Labour Relations (faculty), or a union/association representative for guidance.