Unfortunately the macOS doesn't have a public API for Peter to reliably detect such things.
Typed triggers are best used for text-expansion macros and made unique enough that they won't get activated during normal typing.
'yt; ' or
';yt ' (less the quotes)
So ⌘L then
That's pretty near as fast as your other trigger and solves the problem.
Alternatively you could use a conflict palette for your macros.
Make it a one action palette and give the different sites unique 1 letter/number prefixes to make type-selecting the desired macro simple.
Open Website in Front Browser @ccstone Macros.kmmacros (6.9 KB)
Or you could use a Conflict Palette instead.
Or you could use a Prompt With List action and really go-to-town.
You have many options.