Image style picker is not loading on subwikis

Reproduction steps:

• create a sub wiki
• create a new image style in the subwiki
• create a new page
• insert an image

Expected:

• the new image style is listed at the image configuration step
  Actual:
• a spinner is displayed and an error is displayed in the console

Note:
There is no issue when the sub-wiki does not have any image style.

Displayed errors:
Query http://localhost:8080/xwiki/rest/wikis/s1/imageStyles?documentReference=s1:Main.WebHome fail and the following error is displayed

Uncaught (in promise) 
Object { readyState: 4, getResponseHeader: getResponseHeader(e), getAllResponseHeaders: getAllResponseHeaders(), setRequestHeader: setRequestHeader(e, t), overrideMimeType: overrideMimeType(e), statusCode: statusCode(e), abort: abort(e), state: state(), always: always(), catch: catch(e), … }