I am getting exactly the same but at row 7
I am goin to guess therefore that the problem is in the github data

found the problem - testing

The problem was that there was an emoji character on the first line of one of the PR. I have manually changed that pr and patchtester is working fine now

Not sure if this can be prevented in future or not

Emoji shouldn't be a problem though...

If it really is going to be that big of an issue, then PR descriptions would need to go through the InputFilter's clean method (even with a raw filter, it will strip 4 byte character (i.e. emoji) if required). master...filter-body would be the change needed.

thanks @brianteeman for solving Issue.

And they're not on j3
So I just checked my db and for J3 it is utf8_general_ci
but for j4 it is utf8mb4_unicode_ci

3.5.0 added support for utf8mb4 and more often than not Joomla should be setting your database to that. So unless something in the checks to say the connection needs downgrading to utf8 was messed up in being ported to the Framework there shouldn't be a difference.

Looking into it but so far I see on my test sites (same server)

J3
Database Collation | utf8mb4_unicode_ci
Database Connection Collation | utf8_general_ci

J4
Database Collation | utf8mb4_unicode_ci
Database Connection Collation | utf8_general_ci

Oops bad paste

J3
Database Collation | utf8_general_ci
Database Connection Collation | utf8mb4_general_ci

J4
Database Collation | utf8mb4_unicode_ci
Database Connection Collation | utf8_general_ci

@brianteeman @mbabker The database collation is only used as a default for new tables being added without an explicit collation. It has never been changed by Joomla. Joomla and its utf8mb4 stuff only changed collation for particular tables, but not database collation.
The problem here seems to be the connection collation, not the database collation.

Cleaning up another old issue. I have tested this on the current J4 installation and with the database charset set to utf8 and collation set to utf8_general_ci. A description field with a collation set to utf8_general_ci. The emoji is indexed correctly.

Can someone confirm if this is still an issue? You can use the repository https:/github.com/roland-d/jtest This has 1 issue with an emoji in it.

I have tested it again and it works on the utf8mb4_unicode_ci, which sites running Joomla 4 should have.

Closing this for now. If not we can re-open this issue and check what is going on.