From 38224895f3921dec42c7f20f966fd12ffef8646a Mon Sep 17 00:00:00 2001
From: Will Hunt <github@half-shot.uk>
Date: Mon, 21 Jul 2025 14:56:41 +0100
Subject: [PATCH] Add a comment

---
 src/UrlParams.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/UrlParams.ts b/src/UrlParams.ts
index 3b55ed2a..308d9892 100644
--- a/src/UrlParams.ts
+++ b/src/UrlParams.ts
@@ -389,6 +389,8 @@ export function getRoomIdentifierFromUrl(
   let roomId: string | null = parser.getParam("roomId");
   if (roomId !== null) {
     // Replace any non-printable characters that another client may have inserted.
+    // For instance on iOS, some copied links end up with zero width characters on the end which get encoded into the URL.
+    // This isn't valid for a roomId, so we can freely strip the content.
     roomId = roomId.replaceAll(/^[^ -~]+|[^ -~]+$/g, "");
     if (!roomId.startsWith("!")) {
       roomId = null;