./routes/invoices.tsx

./routes/invoices/$invoiceId.tsx

./routes/invoices/$invoiceId/activity.tsx

./routes/invoices/$invoiceId/activity/$activityId.tsx

All these routes will be matched to the same hierarchy that ends with $activity.tsx

But not the following because $activity.tsx has siblings whose file names matches exaclty with the route leaf(all, latest).

You can access router parameters using "useParams". So in this page:

invoiceId is something

activityId is something-else

You can use 'useSearchParams' to access the query parameters.In this page parameter 'q' has following value(s)

["aaa"]