I frequently use "The Waffle" button to open a new browser window in a different Google application within the same Google account. This is particularly useful when you are logged into multiple Google accounts in a single browser.
This button is presently still visible on the main pages for given apps (e.g. the list of files in Sheets or Drive). However, it used to appear on document pages too. In the last month or so, it has been removed from there. Now the "title bar" in Docs, Sheets, etc looks like this:
How do I get The Waffle back on document pages??