Upload it at some file hoster or image hoster like "imgur",
Postimage
ImageShack
Kek.gg
ImgBox
Unsee
PicPastePlus
ImgPile
And then link it in the comments via the image tag above the edit box:
Code:
[IMG ]https://i.imgur.com/bQ7oflO.png[/IMG]
-->Without space after [IMG, had just added it here so that it does not render as an image and shows the [IMG ] and closing [/IMG] tags
Or put the files on your GoogleDrive, Dropbox, OneDrive or other cloud drive you are using and share the link with the dev.
This won't work with the [IMG ] tags then!