• local * (ps you need an edit button)!

Extension can't set a local page as the new tab page, but you can possibly do this via an autoconfig file.

• https://support.mozilla.org/en-US/kb/customizing-firefox-using-autoconfig

See this thread:

• [/questions/1251199] How do I set my local HTML page as a homepage?

// autoconfig.cfg needs to start with a comment line var {classes:Cc,interfaces:Ci,utils:Cu} = Components; var newTabURL = "file:///<local-file-path>"; aboutNewTabService = Cc["@mozilla.org/browser/aboutnewtab-service;1"].getService(Ci.nsIAboutNewTabService); aboutNewTabService.newTabURL = newTabURL;

Firefox 75 and newer need updated code (aboutNewTab instead of aboutNewTabService), see:

• [/questions/1283835] firefox.cfg no longer overwrite new tab content

// autoconfig.cfg needs to start with a comment line
var {classes:Cc,interfaces:Ci,utils:Cu} = Components;
/* set new tab page */
Cu.import("resource:///modules/AboutNewTab.jsm");
var newTabURL = "file:///G:/Documents/Newtab.html";
AboutNewTab.newTabURL = newTabURL;

// autoconfig.js start with a comment line and uses Unix line endings (LF and not CR/LF)
pref("general.config.filename", "autoconfig.cfg");
pref("general.config.obscure_value", 0);
pref("general.config.sandbox_enabled", false); // disable sandbox

To use Autoconfig, place two files into the Firefox directory where firefox.exe is located.

• (64-bit Firefox) "C:\Program Files\Mozilla Firefox\"
• (32-bit Firefox) "C:\Program Files (x86)\Mozilla Firefox\"

The autoconfig.js file that specifies to use autoconfig.cfg is placed into the "defaults\pref" directory where the channel-prefs.js file is located.

The autoconfig.cfg file is placed at the top level of the Firefox directory.

• autoconfig.cfg and autoconfig.js need to start with a comment line (//)
• autoconfig.js needs to use Unix line endings (LF instead of CR/LF)

See also:

• https://support.mozilla.org/en-US/kb/customizing-firefox-using-autoconfig

I really want it to work out the box like it should like it used to like it does on my current dev ff version im on now! just i want the newest 1 so i get updates so fixit! i dont want addons or walk arounds of any kind! the responsabilty for security is down to me to toggle a button saying i accept responsilibity! or whatever simples logic fix it!

This isn't directly supported, only http:// and https:// is supported and not about: pages and file:// URIs. I think that New Tab Override can workaround this by storing a copy of the local file in its own storage and use that instead of opening the file directly.

• https://addons.mozilla.org/firefox/addon/new-tab-override/

store a local HTML file in the extension's storage and use the content as new tab content

overide worked once but no more! again ff started well and in name of security it prevents things like overide from working so ff are bad at what they do if they really cared about security they would prompt for password when chage of setting is detected a password setup when you install ff to start with there you go thats how easy security is!