Attachments are auto-sized to 600px width when uploaded as attachments, or when they are inserted in-line within a post. This is done to keep the forum structure intact.
Thumbnails will be auto-generated when necessary.
These thumbnails are then clickable and they will expand to show the full version of the image in a gallery view.For attached files, The size limit per image is 500kb, with a max of 2500kb per post. I recommend using an image editing software such as Photoshop to optimize your image sizes, or even easier, upload them to a site like
imgur and link them from here.
