Work. I count 5 profiles on my current laptop. I like to compartmentalize my work/external projects, so I don't mix things like search histories, multiple Google accounts, etc.
These are the profiles I currently have:
1. Default, personal. My personal Gmail and other sites.
2. Non-profit that I run, signed in to its Gmail and other email account, etc
3. 3 profiles for different volunteer/contract roles, each signed in to their Gmail and other accounts.
One example - my shopping profile runs the extensions Rakuten/Honey to find coupon codes. I don't want those running on every single page I load outside of the shopping intent, so I use a separate profile.
Firefox's containers don't allow for limiting extensions, so you have to use profiles. Chrome only has profiles.
These are the profiles I currently have:
1. Default, personal. My personal Gmail and other sites.
2. Non-profit that I run, signed in to its Gmail and other email account, etc
3. 3 profiles for different volunteer/contract roles, each signed in to their Gmail and other accounts.