Sale of primary residence, any upper bound exemption on the capital gains, or unlimited?

Question if there is any upper bound at all on the capital gains exemption from the sale of a primary residence property.  For example:

- purchased home as primary residence for $200,000 (year 2000)

- remained living there for 21 years as primary residence

- sell house in year 2022 for $1,500,000 , resulting in $1,300,000 capital gains.

The Gov't of Canada website doesn't state an upper bound on the capital gain exemption, but an accountant I asked mentioned that there is a $1,000,000 cap on the capital gains exemption (i.e. not unlimited).  I wasn't sure what is the correct answer.  Does anyone know?   TY!