Installability doubt (Lighthouse)

First: congratulations and thanks for the plugin, very simple to configure and complete to make a site PWA-ready.

Recently (with the Chrome versione 89 and other Chromium-based browsers as Brave, Microsoft Edge, Vivaldi) when I checked with Lighthouse throught the Developer Tools (withany of these browsers), under the title “Installability” there is a warning that says “Page does not work offline. The page will not be regarded as installable after Chrome 93, stable release August 2021.“.

Now the question is: There is some errors by me or there will be an update from the plugin’s author?

The page I need help with: [log in to see the link]