Attachments added to comments are lost

Reproduction steps:

• Create a change request
• Click on the comment button in the change request
• Drag&drop an image, or upload it using the image button
• Save the comment
• Perform a hard refresh of the change request

Expected result:

• the image is displayed when saving the comment, and it's still displayed when performing the hard refresh. The attachment should be listed when checking attachments of the CR

Obtained result:

• the image is displayed when saving the comment, but it disappears when performing the hard refresh. The attachment cannot be found in the list attachments of the CR