We have an image header that has style="width:100%".  As a teacher and admin, the image shows as expected.  Even when "viewed as student" the image looks correct.

However, when I log in as an actual student the image has the width:100% stripped out and the image displays too large.

It isn't all or only css though.  If the image is given style="width:1000px", the image displays as expected for all users.  In fact, if I have style="width:100%;max-height:300px" only the width style is removed.  Also, if I use just the not CSS width = "100%", it strips that out as well.   

Also, to be clear, when I say "strips out", I mean upon rendering.  When I go back to edit, the code is still there.  

Overview:

<img src="x.jpg" width="850px" /> <-works

<img src="x.jpg" style="width: 850px" /> <- works

<img src="x.jpg" width="100%" /> <-does NOT work

<img src="x.jpg" style="width: 100%" /> <- does NOT works