Uniswap/pancakeswap front end testing

I have built a contract that works successfully on ganache in a bsc-mainnet-fork. I can add liquidity, exchange tokens, etc. all via the console and/or with scripts. However, my contract has transaction tax so if I do not use the SupportingFeeOnTransferTokens variation of the swap functions the transactions fail (as expected).

How does the uniswap/pancakeswap front end know to use the SupportingFeeOnTransferTokens functions when interacting with my contract? Furthermore, is there a way to fork pancakeswap v2 to do this kind of local testing? I know that there is no front-end test net to use

bumping this for visibility