A client on EE2.5.2 has just found that they can't login with Safari 7.1 on OSX. Chrome and FF work fine, but in Safari, pressing Submit just returns them to the blank login page. I tried changing "Control Panel Session Type" to "Cookies only" but that didn't do it.
I could try upgrading them to 2.9 but don't want to charge them for an upgrade if it's not guaranteed to fix the issue.
Any ideas why this might be happening? Thanks!