Rstudio server 1.4 refuses to run on Ubunto 20.04

[nickschurch]

sudo apt-get install gdebi-core
wget https://download2.rstudio.org/server/bionic/amd64/rstudio-server-1.4.1106-amd64.deb
sudo gdebi rstudio-server-1.4.1106-amd64.deb

Fails with

Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading state information... Done

RStudio Server
 RStudio is a set of integrated tools designed to help you be more productive with R. It includes a console, syntax-highlighting editor that supports direct code execution, as well as tools for plotting, history, and workspace management.
Do you want to install the software package? [y/N]:y
/usr/bin/gdebi:113: FutureWarning: Possible nested set at position 1
  c = findall("[[(](\S+)/\S+[])]", msg)[0].lower()
(Reading database ... 76704 files and directories currently installed.)
Preparing to unpack rstudio-server-1.4.1106-amd64.deb ...
Unpacking rstudio-server (1.4.1106) over (1.4.1106) ...
Couldn't find an alternative telinit implementation to spawn.
Setting up rstudio-server (1.4.1106) ...
useradd: user 'rstudio-server' already exists
Couldn't find an alternative telinit implementation to spawn.
/usr/lib/rstudio-server/bin/rserver: error while loading shared libraries: libssl.so.1.0.2: cannot open shared object file: No such file or directory

The default libssl for ubuntu 20.04 is now 1.1.1j not 1.0 , but even installing the downgraded libs (from http://security.ubuntu.com/ubuntu/pool/main/o/openssl1.0/libssl1.0.0_1.0.2n-1ubuntu5.6_amd64.deb doesn't help).

rstudio-1.3.1093 was working (see other bug from me coming shortly), but a follow up install of this with gdebi after trying to install 1.4 results int he same error, so now thats borked too. What a mess.

[nickschurch]

A solution here is to install libssel1.0.0 from the xenial archives with:

sudo nano /etc/apt/sources.list
deb http://security.ubuntu.com/ubuntu xenial-security main
sudo apt update
sudo apt install libssl1.0.0