Why does Mozilla need google chrome to opperate

Not sure what you're talking about - Chrome, Firefox, Thunderbird? In case it isn't obvious, this is the Thunderbird forum.

I have tried deleting google chrome but when I do my Mozilla will not work.

Chrome and Firefox are not related, except that both are web browsers.

Is firefox not a secure feature?

Firefox is a web browser, and it certainly does have certain security features.

Long before there was a Google Chrome, Mozilla products used the term chrome to refer to the user interface components that surround the content you are viewing. So you may see the word chrome from time to time in error message.

Could you be more specific about the error you're seeing and what you were doing at the time it appeared?

Also, since unresponsive script errors can be caused by Flash, if you are getting those, try disabling the protected mode feature of the Flash player plugin. It has security benefits, but seems to have compatibility issues on some systems. There is a hidden setting for this:

(A) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(B) In the search box above the list, type or paste flash and pause while the list is filtered

(C) Double-click the dom.ipc.plugins.flash.disable-protected-mode preference to switch its value from false to true.

This might not take effect until all Flash has been unloaded for a few minutes, or you close Firefox.

By the way, a safe place to download Firefox is this page (scroll down to your preferred language): https://www.mozilla.org/firefox/all/

But if Firefox never runs normally on your system, you might want to pre-clean it:

(1) Open the Windows Control Panel, Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help surface undisclosed bundle items that snuck in with some software you agreed to install. Be suspicious of everything you do not recognize/remember, as malware often uses important or innocent sounding names to discourage you from removing it. Take out as much trash as possible here.

(2) Supplement your regular security software with several of the scanning/cleaning tools listed in our support article: Troubleshoot Firefox issues caused by malware. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.

Hopefully that will remove any opportunistic malware lying in wait for Firefox.