Getting app cast parse error "line 9: xmlParseEntityRef: no name"

[rdutoit]

Description of the problem

Hi, I've used sparkle for years but had stopped for a while and now using in my new app. did everything exactly, used generate_keys, generate_appcast tools in archive on dropbox. Always worked easily before (with older sparkle.)

Do you use Sandboxing in your app?

NO

Version of Sparkle.framework in the latest version of your app

2.5.1

Version of Sparkle.framework in the old version of app that your users have (or N/A)

N/A

Sparkle's output from Console.app

Error: An error occurred while parsing the update feed. (null) (URL (null))
Error: Line 9: xmlParseEntityRef: no name
(null) (URL (null))

Steps to reproduce the behavior

feed url:
https://www.dropbox.com/scl/fi/v0pdhlya9bv66r6yljxdz/alpharob.xml

Appcast:

<title>backupList+</title> <title>9.1.0</title> Tue, 28 Nov 2023 21:22:31 -0500 9100 9.1.0 10.13