One click on this icon in my dock and Google calendar opens in Firefox from my Dubbo.org G-mail account. This script has chosen the browser and the website and the account that I want to be logged into when I visit the website. This article below describes how to write the script to open a URL in a specified browser. To auto-login as a user see here. To customise the icon see here.
I have four different Google accounts and quite often I find myself in a browser in the wrong account. For example I might be trying to edit my church calendar, which resides in my work Google account, but because I have just been reading my personal mail in Gmail, I am logged into that Google account. In the Chrome browser you can switch accounts by going to the top right and selecting a different account but it’s clunky.
This article below describes how to automatically login to a certain account when you open a URL in a browser. To automate this with a script see here.