Why is my neighbor's Yandex mail and Yandex settings in google chrome?

Question

Google Chrome

Yandex neighbor opens today in Google Chrome, and sees someone else's mail and a "custom" setting of Yasha's main page. I hear an exclamation, when I come closer I understand that this is my mail. But damn it, how did he open it in a beech tree? To say that I was stunned is to say nothing. It's good that at least not all 350 tabs have opened yet ...
By the way. I use google chrome (I also check this mail there), OSX Maverics (macbook), WI-FI, and punto switcher (I know what it is g ... on a stick, but I spit on it because of convenience).
Now I think that this is all the fault of punto .... I climbed all the settings, up to flash cookies. I came across another interesting request from Yandex to my webcam and microphone (I can count on my fingers the times when I turned on the webcam).
Or is Google doing something? I understand that by agreeing to their "privacy policy" we agree to SUCH, but to open my mail in someone else's browser, forgive it too much.
I have remote access disabled, file sharing too, only in chrome there was an extension for collaboration with an authorized iPhone (via Google mail).
Maybe someone has some ideas? After all, in fact, it's terrible ...
PS A joke from a neighbor is excluded; I didn’t even hold his beech in my hands, not to go to the post office through it.

Answer 1

Possibly like this: chrome://settings/passwords

Answer 2

From the point of view of Yandex, you have one IP, one axis (?) and one browser. The only difference is in cookies. Maybe Yandex got bugged and he thought that cookies are not so important? :)
Another version (just as delusional): you logged in at the same time, your router turned over in the NAT table, and it gave your cookies to its session.
If reproduced, write to Yandex. Google IMHO has nothing to do with it.

Answer 3

Perhaps you have chrome://settings/syncSetup configured with the same account on both computers?