Done in #10928

Is this still needed? feel free to close if not...

I guess this is useless as it will be removed with #6093 in Matomo 4.

This issue is related to the json2 API data export format, an alternative to the standard json format, which is currently un-documented but used in the app see: https://github.com/matomo-org/matomo/search?q=format%3Djson2&unscoped_q=format%3Djson2

We announced in 2.16 release:

The 'json' API format is considered deprecated. We ask all new code to use the 'json2' format. Eventually when Piwik 3.0 is released the 'json' format will be replaced with 'json2'. Differences in the json2 format include:
A bug in JSON formatting was fixed so API methods that return simple associative arrays like array('name' => 'value', 'name2' => 'value2') will now appear correctly as {"name":"value","name2":"value2"} in JSON API output instead of [{"name":"value","name2":"value2"}]. API methods like SitesManager.getSiteFromId & UsersManager.getUser are affected.

It was fixed in #10928 and matomo-org/matomo-log-analytics#160 but reverted in #10959 and
matomo-org/matomo-log-analytics#161

because #10928 (comment)

-> if i understand correctly, the next step is to make the Mobile Apps use json2 format?

Wondering if we really want to change this? is it worth the trouble of breaking BC for maybe quite a few api consumers...

I don't think it is much of a priority?

Need to make sure JSON2 doesn't change an expected response of [{}] to {}