TL;DR Remove the Novak Infusionsoft SDK plugin if the Systasis GF Infusionsoft Feed is the only user.
The Infusionsoft SDK contains the glue connecting the feed to Infusionsoft. With the release of PHP V8, this version will stop working.
Version 2.4 incorporates another, better supported version of this connector. This plugin’s configuration now depends on the presence of the Novak Infusionsoft SDK plugin.
Will this plugin be the only user of the Novak plugin?
YES == > Deactivate and uninstall the Novak Infusionsoft SDK plugin.
NO == > This plugin will use the app name and API key values configured by the Novak plugin.