Following up to an issue reported on frwiki [[ https://fr.wikipedia.org/wiki/Wikip%C3%A9dia:Questions_techniques/semaine_52_2022#Tri_de_colonne_presque_impeccable | here ]] (and [[ https://fr.wikipedia.org/wiki/Discussion_mod%C3%A8le:Date#souci_tri_de_colonne | here ]]).
A cell that contains this:
```
<time … data-sort-value="1840">1840</time><br><time … data-sort-value="1889">1889</time>
```
Ends up with this sort value: `18401889`.
The issue has been fixed locally by adding a space next to the `<br>` tag:
```
<time … data-sort-value="1840">1840</time> <br><time … data-sort-value="1889">1889</time>
```
So the sort value has become: `1840 1889`.
An improvement in Tablesorter, when parsing the nodes to build the sort value, would be to replace the `<br>` tags with a space, rather than an empty string. See the code [[ https://gerrit.wikimedia.org/g/mediawiki/core/+/933c7db473fe791c2f0ec8e02e4f3b5f95506631/resources/src/jquery.tablesorter/jquery.tablesorter.js#65 | here ]].
Also, we may want to normalize and remove the consecutive spaces, by adding something like `result.replace( /\s+/g, ' ' )`.