Thanks for the link. So it's a subset of kdeconnect/gsconnect for Linux/Android [1] [2] [3]. I'm using it to share files and tabs from my phones / tablets to my pc and viceversa. It does many other things including sms from the pc. It works with any browser or with no browser at all. There is no need for an extension.

I'm sure Apple has had that too for a long time and I saw something like that from Microsoft a few days ago.

[1] https://play.google.com/store/apps/details?id=org.kde.kdecon...

[2] https://community.kde.org/KDEConnect

[3] https://extensions.gnome.org/extension/1319/gsconnect/