Not sure, I think you need a certain amount of likes or comments to unlock the upload images button, as for linking an image, in the comment section, check the icons and click on the image on, then post the image's url
upload the image to a server so that it has a url. for example, meme machines let you upload images which then gain a url you can copy paste. uploading to discord then opening the image in browser will also provide an img url you can copy paste.
after 5 comments in forum not these profile posts, then you can upload images raw from your computer into the forum. anti bot measure
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