From v2.9.0beta2 on a multisite, multicontainer setup:
== 20220304162250 EnableUnaccentExtension: migrating ==========================
-- enable_extension("unaccent")
Docker Manager: FAILED TO UPGRADE
#<RuntimeError: RuntimeError>
/var/www/discourse/plugins/docker_manager/lib/docker_manager/upgrader.rb:203:in `run'
/var/www/discourse/plugins/docker_manager/lib/docker_manager/upgrader.rb:101:in `upgrade'
/var/www/discourse/plugins/docker_manager/scripts/docker_manager_upgrade.rb:19:in `block in <main>'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/activesupport-6.1.4.1/lib/active_support/fork_tracker.rb:10:in `block in fork'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/activesupport-6.1.4.1/lib/active_support/fork_tracker.rb:8:in `fork'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/activesupport-6.1.4.1/lib/active_support/fork_tracker.rb:8:in `fork'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/activesupport-6.1.4.1/lib/active_support/fork_tracker.rb:27:in `fork'
/var/www/discourse/plugins/docker_manager/scripts/docker_manager_upgrade.rb:6:in `<main>'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.10.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:48:in `load'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.10.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:48:in `load'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/railties-6.1.4.1/lib/rails/commands/runner/runner_command.rb:42:in `perform'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/thor-1.2.1/lib/thor/command.rb:27:in `run'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/thor-1.2.1/lib/thor/invocation.rb:127:in `invoke_command'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/thor-1.2.1/lib/thor.rb:392:in `dispatch'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/railties-6.1.4.1/lib/rails/command/base.rb:69:in `perform'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/railties-6.1.4.1/lib/rails/command.rb:48:in `invoke'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/railties-6.1.4.1/lib/rails/commands.rb:18:in `<main>'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.10.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in `require'
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.10.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in `require'
bin/rails:18:in `<main>'