Because Ignition uses enterprise certificates, Apple may revoke them. If the app stops opening, you will need to wait for Ignition to re-sign it, or use App Cloner to bypass this, as described in.
It looks like you're referring to a post about and jailbreaking . app.ignition.fun jailbreak
: Apple frequently disables the enterprise certificates used by Ignition. If the app or your downloaded jailbreak stops opening, you must wait for a "re-sign" or use a computer method like AltStore. Because Ignition uses enterprise certificates
Jailbreaking is a process that allows users to remove software restrictions on their iOS devices, giving them more control over their device and allowing them to install apps not available on the App Store. app.ignition.fun jailbreak