Homepage shouldn't be used in lieu of the New Tab page in Firefox 41-plus versions. In Firefox 41 the browser.newtab.url pref is gone from the Firefox program files. That pref was being abused by malware so frequently that Mozilla decided to remove that pref to eliminate that type of hijack.

You probably have an extension installed such as one of these which restored that preference. https://addons.mozilla.org/en-US/firefox/addon/new-tab-override/ https://addons.mozilla.org/en-US/firefox/addon/new-tab-homepage/ https://addons.mozilla.org/en-US/firefox/addon/classicthemerestorer/

Note: If you look in about:config and see the browser.newtab.url pref, it isn't being used - don't be fooled by its' mere presence in the advanced prefs 'config' display. The update to Fx 41 wouldn't have removed that pref, but Fx 41 ignores it when it was set with an earlier version. The extensions that 'restore' that feature to Firefox use their own pref for changing the New Tab page, which won't be that exact pref.

Ah, thats too bad. But safety before everything. That is good. Classic theme restorer i already had ;) love it actually. I like the old theme so much more. The new tab override doesnt work for me.. Well, guess i have to live with it, and use the favorites. Thank you for your awnser.

Don't use more than one of those extensions.

When using the Classic Theme Restorer extension, go into CTR options > Tabs (1) section and set your preference for the new tab URL there.