Just to confirm my investigation I asked my host to check and this is their response:

I have taken a look at the site for you with some of my colleagues here.

The site/database is already configured as you require:

MariaDB [_]> SET @@character_set_connection=utf8;
Query OK, 0 rows affected (0.000 sec)

I would suggest you raise this with b2 development team for further advice as the database is configured as required!

Kind regards,

Adam

So I am still in the dark. Maybe a fresh upload and overwrite??

Duplicated in next post.

Ok Have hacked /install/index.php to see what is going on

From Line 650 I have now inserted four lines: 659, to 633

if( ! is_null( $old_db_version ) )
{
$expected_connection_charset = $DB->php_to_mysql_charmap( $evo_charset );
if( $DB->connection_charset != $expected_connection_charset )
{
display_install_messages( sprintf( T_('In order to install b2evolution with the %s locale, your MySQL needs to support the %s connection charset.').' (mysqli::set_charset(%s))',
$current_locale, $evo_charset, $expected_connection_charset ) );
// sam2kb> TODO: If something is not supported we can display a message saying "do this and that, enable extension X etc. etc... or switch to a better hosting".
				
[color=blue]echo"Testing &#36;evo_charset<br />";
echo"&#36;evo_charset = " . $evo_charset . "<br /><br />";
					
echo"Testing &#36;DB connection_charset<br />";
echo"&#36;DB connection_charset = " . $DB->connection_charset;[/color]
break;

Hmmm! Codeblock Plugin not working

Ok That's it for today ~ I think ~ Hope as I@ve spend hours fiddling with files and getting no change. So if @fplanque or colleague has any comment that would be great :)

It's only a test site so no loss of data or use, just bugging me.

????

Somehow the site is working and status shows 7.2.0 but there was no move on the install failure and consequently no options to upgrade or choose not to have demo content, so the site is a bit weird.
https://lovejoy.org.uk

Just a test site for 7.2.0

Just looking at this issue again and note the new log entry as described at https://b2evolution.net/downloads/7-2-0-beta#more363908

The log appears to be fine so the question remains why the error message and how did the install jump this error, update the database and install demo content. ??