gem install mysql2 gives error because library missing

[ghost-from-the-past]

(running Tracks on Ubuntu 22.04)

I updated to the last commit then when

bundle update
I get the error
Installing mysql2 0.5.4 (was 0.5.3) with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

current directory: /var/lib/gems/3.0.0/gems/mysql2-0.5.4/ext/mysql2

/usr/bin/ruby3.0 -I /usr/lib/ruby/vendor_ruby -r ./siteconf20220509-100490-a4v9t8.rb extconf.rb
checking for rb_absint_size()... yes
checking for rb_absint_singlebit_p()... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_enc_interned_str() in ruby.h... yes
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers

[ghost-from-the-past]

this was due to a missing library
you must install

sudo apt install default-libmysqlclient-dev

then when

bundle update

everything will work fine