Describe what not worked means. Do you get a failure from Safari that you can share? Does the site even load? Do you fail authentication? What version of Safari?
I use Safari 8.0.2. When I click on a link for Gmail, I can see that Safari starts to go to the link but it stucks at about 15% of the progress line and does not move from there.
When I use the same lnk with Firefox, no problem.
I find also that Safari is also slower than Firefox on other links as well but at least, it gets there.
I have never had an issue with any version of Safari logging into my account at mail.gmail.com. I will check Yosemite and see if something has changed that affects it.
PS, Just tried it in latest Safari in Yosemite and my account goes right in every time.
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