I compared the dataTables.altEditor.free.js files on my test instance and the distribution folder.
They are both v2.0, both dated 2017 - quite different contents
![Groan :groan:](./images/smilies/groan.gif)
My test version has code for "select" amongst many other changes.
I'm not sure why my diff program was not flagging this, that is tbi.
![bash :bash:](./images/smilies/bash.gif)
Nor do I understand how Paul seems to have the later version as well.
But try this version in /interface/lib/datatableseditor/...