Steps to reproduce

1. First, attach an image with an exclamation mark to Confluence page. For example: Donald!.gif
2. Next, use the Rich Text Editor to insert the image. You can use either the new keyboard shortcut ( ! ) or the icon to insert image
3. Save the page
4. The image won't be rendered and you will get the following error:

   Unable to render embedded object: File (Donald) not found..gif|border=1!

5. When you edit the page, you get the following in Wiki Markup mode:

   !Donald!.gif\|border=1\!
   

6. Here are some screenshots to depict the bug:
   • Step1_AddImage.png
   • Step2_ImageInserted.png
   • Step3_AfterSaving.png
   • Step4_PageEditedRichText.png
   • Step5_PageEditedWikiMarkup.png