Debian OpenSSL 1.1.1~~pre6-1 defaults to requiring 2048 bit RSA keys

Francois writes on https://bugs.debian.org/907351:

I get the following error in my logs approximately every 2 hours:

Aug 26 05:05:01 hostname Tor![25963]: TLS error while constructing a TLS context: dh key too small (in SSL routines:ssl3_ctx_ctrl:---)

I tried upgrading to the version in experimental and it also has this problem.

[experimental had 0.3.4.6-rc-1 at that time.]