initial report, in French.

Two Mac OS Sierra users have reported this bug:

1. edit a page using VE
2. click on insert > media
3. pick an image
4. click on "advanced settings" to change the size of choose a frameless option (a user reports he only have that issue for "frameless" option and "basic option" on Sierra 10.12.6)
   1. expectation: you change the options and the image is inserted
   2. reality: the advanced settings window shows a loading bar, endlessly

Some report by @Drongou from the console (?):
`ligne 76959 inserimageNode

case 'mwInlineImage':

if (selectedNode.type === 'mwBlockImage') {                                 null is not an object (evaluating 'selectedNode.type')
       fragment.insertContent([{
           type: 'paragraph',
             internal: {
                generated: 'wrapper'
           }`

The following apparently works:

1. edit a page using VE
2. click on insert > media
3. pick an image
4. insert it
5. double click on the image to edit it
6. go do advanced settings tab and change things
7. exit