Urls to image-files in some specific text-field instances are pointing to the
wrong domain when using multiple domains.
• Only image urls in text-fields in topics, but not subtopics, are affected.
• The bug also affects descriptions of subtopics.
• It is nondeterministic if new textfields or subtopics are affected.
• If a textfield/description is affected, the bug can be reliably reproduced.

A detailed description of the issue can be found here (pdf-file):
https://www.dropbox.com/s/kzic2nmja8gkfc5/moodle_bug%3Awrong_image_url_in_textfields_when_using_mutliple_domains.pdf?dl=0