CGT on foreign currency on brokerage account or Money Market Fund

[megatower25]

I held some dollars on a brokerage account to buy and sell shares and funds. I don't convert the dollar back to pounds between different transactions and may held dollar for a long period, as I plan to continue to invest on dollar base securities.

I understand the foreign currency on a bank account is not subject to CGT (from exchange rate fluctuation), but would the same apply to brokerage, or even one step further, to Money Market Fund (especially those with a constant NAV)?

There is a related but very old thread below but it wasn't conclusive :
https://www.taxationweb.co.uk/forum/viewtopic.php?f=3&t=54848&p=201417#p201417

Any thought or suggestion would be much appreciated.

[AGoodman]

Cash in a brokerage account is still in a bank account so the usual rules would apply.

When you hold a Money Market Fund, you aren't holding currency, you're holding an interest in the fund (be it shares or units of a UT).