<p>When I login to StackOverflow and switch to have a look at CrossValidated, I need to login again.</p>

<p>If I first go to CrossValidated, I am already online at StackOverflow automatically.</p>

<p>If I login to StackExchange I am also online at both sites directly.</p>

<p>It's not a big deal, I can always login at CrossValidated (or StackExchange) but still wanted to know if I overlooked a checkmark somewhere (about shared login). Any ideas?</p>

<hr>

<p><strong>Edit</strong></p>

<p>To clarify the different scenarios:</p>

<p><strong>Scenario A</strong></p>

<p>1st.: Login at stackoverflow.com:</p>

<p>→ new login needed at stats.stackexchange.com</p>

<p>→ new login needed at tex.stackexchange.com</p>

<p>→ automatically logged in at askubuntu.com</p>

<p><strong>Scenario B</strong></p>

<p>1st.: Login at stats.stackexchange.com:</p>

<p>→ automatically logged in at stackoverflow.com</p>

<p>→ automatically logged in at tex.stackexchange.com</p>

<p>→ automatically logged in at askubuntu.com</p>

<p><strong>Scenario C:</strong></p>

<p>1st.: Login at stackexchange.com:</p>

<p>→ automatically logged in at stackoverflow.com</p>

<p>→ automatically logged in at stats.stackexchange.com</p>

<p>→ automatically logged in at tex.stackexchange.com</p>

<p>→ automatically logged in at askubuntu.com</p>

<p>It is noteworthy that I can see my sites (and reputation) in the drop down menu, even though not online in all sites. In the following screenshot I am logged in (only) to stackoverflow.com, but get also <em>notifications (rep change)</em> from CrossValidated. If I click on CrossValidated (or TeX-LaTeX), I am redirected to the corresponding login site. This is what I previously described as <em>Scenario A</em>.</p>

<p><a href="https://i.stack.imgur.com/3eQBN.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3eQBN.png" alt="enter image description here"></a></p>
