I had a "little emergency" fund of ~5k cash in my HISA and held my "big emergency" fund of 21k in my TFSA for about 5 years in VSB short term bonds, where it made under 1k in gains and interest. After I maxed out my TFSA in VCN on top of the 21k VSB, I started transitioning my emergency fund from TFSA by building up my HISA account to 21k, and then sold off the VSB in my TFSA to buy VCN so it can grow.
TFSA should ideally be all stocks due to tax free capital gains, but your emergency fund should be cash, easily accessed. Take steps to get there.