Let's say we want our apple-app-site-association rules to match only <domain>/anypath/ but not matching any more additional URL components based on it (such as <domain>/anypath/anotherpath/).
What we have to write in apple-app-site-association is:
paths: [
"NOT /*/?*",
"/*/"
]
?- matching one character
*- matching zero to any characters
The ?* pattern above implies there is more than one path component (at least one path component) matched.
The interesting thing is, if * is defined in the middle of the URL pattern, it does not allow * to match zero characters. (such as /path/*/another/ will not match path/another/).
Only the trailing * would have zero characters matching behavior.
That's why I consider it a trick.