You can have whatever page you want to open when opening a new tab, including a blank page, if that is what you choose.

1. In the Location bar, type about:config and press Enter.
   • The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise!, to continue to the about:config page.
2. Type browser.newtab.url in the search box.
3. Double-click the browser.newtab.url preference and change the url from about:newtab to about:blank. Alternately, you can change it to about:home for the Firefox Google home page, or type in your preferred home page, for example google.com.
4. Click OK and close the about:config tab.
5. See - https://support.mozilla.org/en-US/kb/new-tab-page-show-hide-and-customize-top-sites

Setting the homepage that opens on starting Firefox - https://support.mozilla.org/en-US/kb/How%20to%20set%20the%20home%20page

Firefox will always open the home page in a new window (File > New Tab > New Window).
To avoid that you would need to open a bookmark with the location set to about:blank in a new window via a Shift and left-click if you do not want to set the home page to about:blank.

I don't see any other ways to do this within Firefox than those that @cor-el and @TheOldFox told you.

On the other hand, there may be an add-on that will enable you to do this without having to edit about:config.

Note that you can force a specific page to open if you start Firefox via a shortcut that has that URL appended.
So you can use that if you do not use the toolbar Home button that often.
Another possibility is to pin that tab to the tab bar so it get opened automatically the next (don't clear the history when Firefox closes).