<p>I can conceive of no reasonable explanation for this (in particular for why osm.org vs openstreetmap.org would make a difference) so to be honest this sounds like a bug in Safari.</p>
<p>As <a class="user-mention" data-hovercard-type="user" data-hovercard-url="/hovercards?user_id=581288" data-octo-click="hovercard-link-click" data-octo-dimensions="link_type:self" href="https://github.com/dieterdreist">@dieterdreist</a> says osm.org will redirect and the cookie will only be sent on the redirected request just as it would be if you had entered openstreetmap.org in the first place. Presumably that window is logged in correctly in both cases?</p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br />You are receiving this because you are subscribed to this thread.<br />Reply to this email directly, <a href="https://github.com/openstreetmap/openstreetmap-website/issues/2194#issuecomment-477944726">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe-auth/ABWnLcn3La1XSLvBs7wAyZlz_v2i-rhxks5vbef7gaJpZM4cSCy7">mute the thread</a>.<img src="https://github.com/notifications/beacon/ABWnLVQSgfVRBnBGAv5F9IDCbmAvTWyXks5vbef7gaJpZM4cSCy7.gif" height="1" width="1" alt="" /></p>
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