Does Android support the 802.11 specifications that allow fast roaming, i.e. prevent dropouts as you move between access points? If so, on what hardware and in what version?
802.11k assists the device in its search for nearby APs that are available as roaming targets by creating an optimised list of channels. When the signal strength of the current AP weakens, device will scan for target APs from this list.
802.11r authenticates more quickly through Fast Basic Service Set Transition (FT).
802.11v allows the network’s control layer to influence client roaming behaviour by providing it the load information of nearby access points. Device takes this "BSS transition management" information into account when deciding among the possible roam targets.
Apple's iOS does, as documented here and here. Windows 10 does if the WiFi adapter supports it as documented here and here (suspect latter is currently out of date with respect to PSK & open networks).
Some Samsung models do, as documented here.
But I can't find anything on stock Android (Google Pixel).