I still can't add images to questions here on this forum, I hit image upload (ctrl-g) it uploads and shows the image in a separate window and then the only thing I can click is "cancel and add another image". Or I can click outside the upload window, but then it does not upload. I can't click "use this image" or anything that would confirm the upload. I'm on a Mac using Safari (Version 8.0.7 (10600.7.12))
You can only upload images in a supported format: jpg, PNG, tiff, bmp or gif.
If you try to upload an unsupported file type, should show you a warning :
It's possible that the button is just hidden at the bottom of the window. Lastly, try a different browser to find out if it's a browser compatibility issue.
Images are limited to 2Mb in size. For larger images or unsupported formats consider uploading to a different host and adding the link to it on your post.