There absolutely is something special about most of these IPs. There are blocks that are reserved only for use in private networks. IETF standards for IPv4 on this topic have been in place for decades:
No, there isn’t anything special about them from a browser’s perspective. They have been reserved so they can be re-used across private networks without conflicting with routes on the Internet. An address in the rfc1918 space isn’t magic and a shitload of corporate/campus/etc networks depend on treating them just like any other IP address when you load stuff up in a browser.
If a page loads a resource from a private address, it can easily be a local cache on the network. It can also be a dashboard like the example I gave you.
Example:
local.dashboard.example.org resolves to 192.168.255.244
dashboard.example.org resolves to some public address and web server that hosts a page that loads resources from local.dashboard.example.org
https://en.wikipedia.org/wiki/Reserved_IP_addresses
https://tools.ietf.org/html/rfc1918