Steps to reproduce:

• Create a page and put a Team Cal macro on it - or go to https://pug.jira-dev.com/wiki/display/~jturnquist/2016/02/15/Test+blog+post
• Click "Watch" or "Watching"
• Click "Manage Watchers"

Result:
Sometimes, the list does not load, showing a spinner for all eternity. This is because it makes a request without the pageId. Sometimes it works. Try refreshing and reproducing a few times.

When it doesn't work, you'll see a 404 to:

/wiki/json/listwatchers.action?atl_token=6e3812c74dc7283aba25791246ce87dc9ed7512f&_=1455255630982

When it works it will make a successful request to

/wiki/json/listwatchers.action?pageId=524292&atl_token=6e3812c74dc7283aba25791246ce87dc9ed7512f&_=1455255600041