`"installed"` event would be needed

[christianliebel]

As a developer, I may not want to display the install button again after the installation has completed. So, an installed event would be helpful, allowing me to store a hint in a cookie/local storage, so I don't show the button again (similar to the appinstalled event).

[LiaHiscock]

I'm interpreting this request as an ask for an additional API that informs you whether your site is installed.

Also worth noting -

• This would only be available for same origin requests -- is that the scenario you're envisioning as well?
• navigator.getInstalledRelatedApps is available -- are there gaps in this that don't meet your developer needs?

[christianliebel]

@LiaHiscock This is a result of our discussions during TPAC (search for "opens, user cancels or whatever").

As an author, I may not want to show the install button again after the user has installed my site once. So, I need a signal that my site was installed.

Only having this for the same-origin case seems fine.

navigator.getInstalledRelatedApps is a Chromium-only API. If I remember our TPAC discussion correctly, neither WebKit nor Gecko is interested in shipping this.