I tried putting an inline image in a post on my iPad Air2 with iOS 8.4. As soon as I tap the photo icon at the top of the WYSIWYG panel, Safari immediately closes. The problem was repeatable several times, and continued through a reboot cycle.
Shoulda bought Windoze.
If the image is already uploaded somewhere you can just manually typearound the url. Pushing that button generates a popup dialog which appears to annoy SAFARI in that version. Happens to me as well so it's not just you.
Damn apple.
There's a lot of things safari just won't do.