System and IINA version:

• macOS 13.6.3
• IINA 1.3.4

Expected behavior:
IINA correctly handles a % character in a URL.

Actual behavior:
When running under macOS Ventura (and earlier releases) if a URL contains an encoded % character (%25) IINA will fail to open the file or stream.

This was uncovered during the investigation into issue #4861.

@xfoxfu provided the following example:

Opening this URL in Firefox:

iina://weblink?url=https://example.com/%25foo%20bar.mkv

Fails reporting the URL can not be percent encoded:

14:25:51.188 [iina][d] Parsing URL iina://weblink?url=https://example.com/%25foo%20bar.mkv
14:25:51.188 [player0][e] Cannot add percent encoding for https://example.com/%foo bar.mkv

Steps to reproduce:

• Running under Ventura, enable logging in IINA

• Open the URL given above in Firefox

• Look for the message shown above in IINA's log file

• MPV does not have this problem.

This is an issue with IINA code. I have not checked if mpv also has this problem.

How often does this happen?
Every time.