Empty page title causes broken attachment links when the page title is changed

Bug Background

1. This issue is caused by CONF-17414, where empty title can exists within Confluence pages due to Doc Import feature
2. Once the Confluence instance has this untitled page, there could be a situation where users want to fix the bug by finding the untitled page and rename it.
3. Although this can be done, it will break some other pages with attachment links in it within the same space.

Steps to reproduce

1. Reproduce CONF-17414 bug
2. Create a page with the following Wiki Markup:

   [^AnyAttachment.png]
   

3. Attach the AnyAttachment.png file to the page
4. Rename the untitled page (can access the page through direct link)
5. The page with the attachment will break with the link looking like the following:

   [NewTitleOfTheUntitledPage^AnyAttachment.png]
   

Findings

This happens to all pages in the space where the Untitled page resides

Workaround

As a workaround, you might want to use the Global Search and Replace Plugin to search and replace the links.