Block Speculative pre-connections in Firefox

[baziroll]

Speculative pre-connections
To improve the loading speed, Firefox will open predictive connections to sites when the user hovers their mouse over thumbnails on the New Tab Page or the user starts to search in the Search Bar, or in the search field on the Home or the New Tab Page. In case the user follows through with the action, the page can begin loading faster since some of the work was already started in advance. To disable this feature:

1. In the address bar, type about:config and press EnterReturn.
   • The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise!I accept the risk! to continue to the about:config page.
     
2. In the about:config page, search for the preference network.http.speculative-parallel-limit.
   
3. Observe the Value column of the network.http.speculative-parallel-limit row.
   • If it is set to 0 then do nothing.
     
   • If it is set to a different value, double-click on it to set it to 0.
     

https://support.mozilla.org/t5/Protect-y...onnections