OpenSearch missing i18n stopwords

[vandijkstef]

Preconditions and environment

• Magento 2.4.8-p1
• PHP 8.3
• OpenSearch

Steps to reproduce

Use opensearch on a non en_EN store, preferably a locale defined in module-elasticsearch/etc/stopwords/stopwords_xx_XX.csv.

Expected result

Search excluding terms as defined in module-elasticsearch/etc/stopwords/stopwords_*.xml

Actual result

Search excluding en_EN stopwords ('and') but is including nl_NL stopwords ('en').

en_EN 'A and B' or 'A B' produce the exact same results. nl_NL 'A en B' or 'A B' should produce the same results, but the first term returns 10x the results.

Additional information

Within module-opensearch, no reference is found to "stopword".

Module-elasticsearch has default stopwords for various different languages available.

Possible relevance to #39809

S2 severity due to too many search results might cause the results page to have 5XX-errors.

Release note

No response

Triage and priority

• [ ] Severity: S0 - Affects critical data or functionality and leaves users without workaround.
• [ ] Severity: S1 - Affects critical data or functionality and forces users to employ a workaround.
• [x] Severity: S2 - Affects non-critical data or functionality and forces users to employ a workaround.
• [ ] Severity: S3 - Affects non-critical data or functionality and does not force users to employ a workaround.
• [ ] Severity: S4 - Affects aesthetics, professional look and feel, “quality” or “usability”.