Icon labels in buttons in Google Mail (Gmail) are missing / not showing / not displaying.
The Cause:
You have probably blocked the following URL address in the HOSTS file:
ssl.gstatic.com
Sometimes forum users give you a list of addresses to block in the Hosts file, for various reasons. Make sure you understand where those URLs point to, if possible.
The Solution:
1. Open the file C:\Windows\System32\Drivers\etc\Hosts in Notepad or Notepad++ (make sure the file is not READ ONLY). Note: This file has no extension.
2. Remove the line from your Hosts file (or put a # at the beginning)
The line most likely looks like this:
127.0.0.1 ssl.gstatic.com
or
0.0.0.0 ssl.gstatic.com
3. Save the HOSTS file (set to READ ONLY, if desired).
4. Refresh the tab in your browser and Gmail should be back to normal. Problem solved.