Telegram allows sharing links with location. Telegram-desktop currently
invokes Google Maps on those coordinates when clicked.

To better protect user privacy, it is better to use OpenStreetMap (like e.g.
Telegram-FOSS mobile app already does)

The attached patch changes telegram-desktop so. Tested on Debian Stable
(Bookworm) telegram-desktop 4.6.5+ds-2+b1, but applies to Sid version
telegram-desktop_4.14.9+ds-1.1 too.