Trying to insert an image into a answer field of a lesson question page (multiple choice type), using the "Insert/Edit image" button of the TinyMCE editor, a dialog shows up allowing to give an image URL, but there's no option to upload an image using the file picker. This limits the images that can be inserted a

Note that there IS an option to upload an image using the file picker in the dialog that shows up when inserting an image into the page's question text (outside the answer fields).

To reproduce:

1) Create new lesson: Settings don't matter.

2) Insert new question page. Multichoice type.

3) Fill in the required fields. Go to the "Answer1" field. TinyMCE editor doesn't show up because the field type is "Moodle auto-format" by default. Change the field type to "HTML format". Save the page and re-edit it. Now the "Answer1" field is surrounded by the TinyMCE editor. Try to insert an image here using the toolbar button. Try to insert one in the page contents field and you can see the difference.