I know that Tor is based on Firefox and since Firefox has added support for ECH (Encrypted Client Hello)/secure SNI (server name indication) for quite some time now, I expected Tor browser to do the same. However, according to some tests I and a friend of mine did on my devices and one of theirs, neither Tor desktop nor Tor mobile (Android) seem to support ECH. I don’t know if this is a bug or an intended feature, so I figured I might as well ask here and it case it proves to be the former, file a proper bug report.
P.S. Mozilla’s ECH settings were available (at least for the desktop client which I checked) as described on Mozilla’s wiki page about ECH
Tools used for checking ECH status: