Mozilla Firefox - Load one tab at a time one after another disable multitasking

Firefox on Linux loads all tabs together at the same time by default. The result of this when opening a lot of heavy tabs is that the system cannot take it and that the browser becomes slow and unresponsive and that no tab seems to finish.

There is a very useful plugin that solves this called Load Background Tabs Lazily by kgersen:

https://addons.mozilla.org/en-US/firefox/addon/load-background-tabs-lazily/

By default it loads one tab at a time, exactly what is needed.