With a little tweak, you can open any website using a hotkey in Google Chrome browser. Here's how to do it.
Open your browser settings and go to the Search engine section or simply open this link
In this section, expand Manage search engines.
Click the Add button and in the window that appears, specify the site data that you want to open with hotkey.
In the Search engine field, specify the name of the site. In the keyword field - the key combination for opening the site. In the URL field - the address of a website.
Click Add and now if you type a keyword in the Omnibox, you can quickly go to the site.
To delete a site, go back to the Search Engine Management section
chrome://settings/searchEngines and delete it.
For the Firefox browser, unfortunately, there is no such setting.