jsoncallback API parameter doesn't work with getBulkRequest

[Findus23]

reported in https://forum.matomo.org/t/api-getbulkrequest-returns-null-with-callback-parameter/40550

when I use the getBulkRequest Method with Matomo 4.1.1 and append the &callback or &jsoncallback Parameter, the array values in the response will always be null. This used to work with matomo 3.14.0

example URL:

works:
https://demo.matomo.cloud/index.php?module=API&method=API.getBulkRequest&format=json&token_auth=anonymous&urls[0]=method=VisitsSummary.getVisits&idSite=1&period=week&date=today
doesn't work:
https://demo.matomo.cloud/index.php?module=API&method=API.getBulkRequest&format=json&token_auth=anonymous&urls[0]=method=VisitsSummary.getVisits&idSite=1&period=week&date=today&jsoncallback=test