how to install safari 11.0 into iMac OSX 10.9.5

I would like to install Safari 11.0 into my iMac (OSX 10.9.5).

Safari now is 9.1.3.

My proof reading of a manusript for publication runs only on Safari 11.0.

I have just accidentally installed Safari 12.1.1 free from a sight but when I try to run it the computer rejected by saying that it is from an unknown site. I was my mistake in two parts; it must be 11.0 exactly to run the proof and I should not have trusted the site. Now I don't know how to uninstall it. It is another story.

If I may go back to the important question. Can I install Safari 11.0 safely ?

I have plenty of hard disk space about 850 GB out of 999 GB.

I would appreciate your advice and guidance.

shinichi17

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