How to install a developer add-on to another Gmail account?

Question

I have developed a simple Gmail add-on, I have Published it using a manifest. Finally, I got "Get ID link for the Head Deployment", from this development id I have installed it to my current Gmail account, it is working perfectly. The problem was by using development id; we need to use it on another Gmail account, but I have followed same steps install-unpublished gmail addon but it is not working.

Updated: i have installed other account also,check ss

but when i open email doesnt appear my addon

Update-2

Answer 1

There is a bug in Gmail add on, when we install the developer add on for the first time. The add on is not showing up for the existing emails.

I faced the same issue. I dont know why it is happening like that, as per my observations, add on is not showing up for the mails which are sent/received before my add on is developed/installed.

Send some new emails and go to sent box, open the new mail which you sent and check for the add on. It should work. It worked for me.

Prerequisites:

1. The add on has to be shared to the other gmail account from the owner of the app script.
2. The add on can not run in Gsuite email account which was developed from personal gmail account. To solve this, I answered in one more post: Getting "Invalid Add-on" when installing unpublished Gmail addon .