Can stick/slush to add checking option to show current receiving address not only in computer but in the Trezor's screen too
Yes, they are working on it. I proposed this to them back in May. Meanwhile you can send small amount first and confirm with the receiver that he has received this small amount before sending the rest of the money. You will pay fee (which is quite small anyway) twice, but you will be safe from browser replacing BTC addresses.
Ahem, unless the browser only replaces the address when the amount is large enough, only when it is being used for the seonc time in N minutes...
(I assumed that the destination address(es) of every transaction to be signed by the Trezor were always displayed on the Trezor window, so that the client could check them independently of the computer and confirm with one of the two buttons. I understand from the comment above that this is not always done, is that it?)
You misunderstood what I said. You always see the destination address(es) on the Trezor display. So there are two options:
1. If the address is replaced by the browser for any amount, you will see incorrect address on the Trezor display for the first transaction and your beneficiary will never receive the small amount from you.
2. If the address is replaced by the browser for big amount only, you will see different destination address (different from the time you were sending the small amount) on the Trezor display when signing the second transaction.
In the first case you loose small amount only, in the second case you don't loose anything because you will decline to sign this bad transaction on your Trezor.
This is a bit clumsy, because you have to check those addresses on the display, BUT this will go away when payment protocol BIP is accepted and implemented in Trezor.