@jandi There's no standard way to represent a link to a post.
So when you click a link in a post in #Pachli -- or other apps -- they generally have some heuristics to decide "Is this a link to a post, or a link to a web page?".
If the heuristic says "It's a link to a post" then the app performs a search for that post on your server and opens the first search result.
Otherwise it opens it as a web page.
The Pachli heuristics are in https://github.com/pachli/pachli-android/blob/4fc6f44f921e53238a5c1e4bbae3474498867882/core/activity/src/main/kotlin/app/pachli/core/activity/ViewUrlActivity.kt#L197-L227