I accidentally made the following API request:
```
https://www.wikidata.org/w/api.php?action=wbformatvalue&generate=text%2Fhtml&datavalue=%7B%22type%22%3A%22wikibase-entityid%22%2C%20%22value%22%3A%20%7B%22id%22%3A%22L10-F3%22%7D%7D&datatype=wikibase-lexeme
==
https://www.wikidata.org/w/api.php?action=wbformatvalue&generate=text/html&datavalue={"type":"wikibase-entityid", "value": {"id":"L10-F3"}}&datatype=wikibase-lexeme
```
i. e., attempting to format a form ID value (`{"type":"wikibase-entityid", "value": {"id":"L10-F3"}}`) as a lexeme datatype.
It results in the following log error:
```
InvalidArgumentException: Not a lexeme ID: L10-F3
/srv/mediawiki/php-1.32.0-wmf.26/extensions/WikibaseLexeme/src/Formatters/LexemeIdHtmlFormatter.php:58
#0 /srv/mediawiki/php-1.32.0-wmf.26/extensions/Wikibase/lib/includes/Formatters/EntityIdValueFormatter.php(44): Wikibase\Lexeme\Formatters\LexemeIdHtmlFormatter->formatEntityId(Wikibase\Lexeme\DataModel\FormId)
#1 /srv/mediawiki/php-1.32.0-wmf.26/extensions/Wikibase/lib/includes/Formatters/DispatchingValueFormatter.php(75): Wikibase\Lib\EntityIdValueFormatter->format(Wikibase\DataModel\Entity\EntityIdValue)
#2 /srv/mediawiki/php-1.32.0-wmf.26/extensions/Wikibase/repo/includes/Api/FormatSnakValue.php(104): Wikibase\Lib\Formatters\DispatchingValueFormatter->formatValue(Wikibase\DataModel\Entity\EntityIdValue, string)
#3 /srv/mediawiki/php-1.32.0-wmf.26/includes/api/ApiMain.php(1570): Wikibase\Repo\Api\FormatSnakValue->execute()
#4 /srv/mediawiki/php-1.32.0-wmf.26/includes/api/ApiMain.php(531): ApiMain->executeAction()
#5 /srv/mediawiki/php-1.32.0-wmf.26/includes/api/ApiMain.php(502): ApiMain->executeActionWithErrorHandling()
#6 /srv/mediawiki/php-1.32.0-wmf.26/api.php(87): ApiMain->execute()
#7 /srv/mediawiki/w/api.php(3): include(string)
#8 {main}
```
I suppose we need to guard against this somewhere, since API usage errors shouldn’t result in uncaught exceptions.